Document and Entity Information	3 Months Ended
Document and Entity Information	Mar. 31, 2015	Apr. 28, 2015
Document and Entity Information
Entity Registrant Name	Transocean Ltd.
Entity Central Index Key	0001451505
Document Type	10-Q
Document Period End Date	Mar. 31, 2015
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		363,350,739
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Operating revenues
Contract drilling revenues	$ 2,000	$ 2,292
Other revenues	43	47
Total operating revenues	2,043	2,339
Costs and expenses
Operating and maintenance	1,084	1,269
Depreciation	291	273
General and administrative	46	57
Total costs and expenses	1,421	1,599
Loss on impairment	(936)	(65)
Loss on disposal of assets, net	(7)	(3)
Operating income (loss)	(321)	672
Other income (expense), net
Interest income	6	10
Interest expense, net of amounts capitalized	(116)	(126)
Other, net	47	(2)
Total other income (expense), net	(63)	(118)
Income (loss) from continuing operations before income tax expense	(384)	554
Income tax expense	83	80
Income (loss) from continuing operations	(467)	474
Loss (loss) from discontinued operations, net of tax	(2)	(8)
Net income (loss)	(469)	466
Net income (loss) attributable to noncontrolling interest	14	10
Net income (loss) attributable to controlling interest	$ (483)	$ 456
Earnings (loss) per share-basic
Earnings (loss) from continuing operations (in dollars per share)	$ (1.32)	$ 1.27
Earnings (loss) from discontinued operations (in dollars per share)	$ (0.01)	$ (0.02)
Earnings (loss) per share (in dollars per share)	$ (1.33)	$ 1.25
Earnings (loss) per share-diluted
Earnings (loss) from continuing operations (in dollars per share)	$ (1.32)	$ 1.27
Earnings (loss) from discontinued operations (in dollars per share)	$ (0.01)	$ (0.02)
Earnings (loss) per share (in dollars per share)	$ (1.33)	$ 1.25
Weighted-average shares outstanding
Basic (in shares)	363	361
Diluted (in shares)	363	361

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS)
Net income (loss)	$ (469)	$ 466
Net income (loss) attributable to noncontrolling interest	14	10
Net income (loss) attributable to controlling interest	(483)	456
Other comprehensive income (loss) before reclassifications
Components of net periodic benefit costs	(13)	(5)
Reclassifications to net income
Components of net periodic benefit costs	5	6
(Gain) loss on derivative instruments		(2)
Other comprehensive income (loss) before income taxes	(8)	(1)
Income taxes related to other comprehensive income (loss)	(2)
Other comprehensive income (loss), net of income taxes	(10)	(1)
Other comprehensive income (loss) attributable to controlling interest	(10)	(1)
Total comprehensive income (loss)	(479)	465
Total comprehensive income attributable to noncontrolling interest	14	10
Total comprehensive income (loss) attributable to controlling interest	$ (493)	$ 455

CONDENSED CONSOLIDATED BALANCE SHEETS (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Assets
Cash and cash equivalents	$ 2,682	$ 2,635
Accounts receivable, net of allowance for doubtful accounts of $14 at March 31, 2015 and December 31, 2014	1,964	2,120
Materials and supplies, net of allowance for obsolescence of $112 and $109 at March 31, 2015 and December 31, 2014, respectively	807	818
Assets held for sale	23	25
Deferred income taxes, net	157	161
Other current assets	210	242
Total current assets	5,843	6,001
Property and equipment	26,740	28,516
Less accumulated depreciation	(6,174)	(6,978)
Property and equipment, net	20,566	21,538
Other assets	696	874
Total assets	27,105	28,413
Liabilities and equity
Accounts payable	619	784
Accrued income taxes	217	131
Debt due within one year	1,024	1,033
Other current liabilities	1,313	1,822
Total current liabilities	3,173	3,770
Long-term debt	8,996	9,059
Deferred income taxes, net	152	237
Other long-term liabilities	1,263	1,354
Total long-term liabilities	10,411	10,650
Commitments and contingencies
Redeemable noncontrolling interest	11	11
Shares, CHF 15.00 par value, 396,260,487 authorized, 167,617,649 conditionally authorized, 373,830,649 issued at March 31, 2015 and December 31, 2014 and 363,346,369 and 362,279,530 outstanding at March 31, 2015 and December 31, 2014, respectively	5,183	5,169
Additional paid-in capital	5,806	5,797
Treasury shares, at cost, 2,863,267 held at March 31, 2015 and December 31, 2014	(240)	(240)
Retained earnings	2,866	3,349
Accumulated other comprehensive loss	(414)	(404)
Total controlling interest shareholders' equity	13,201	13,671
Noncontrolling interest	309	311
Total equity	13,510	13,982
Total liabilities and equity	$ 27,105	$ 28,413

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) In Millions, except Share data, unless otherwise specified	Mar. 31, 2015 USD ($)	Mar. 31, 2015 CHF	Dec. 31, 2014 USD ($)	Dec. 31, 2014 CHF
CONDENSED CONSOLIDATED BALANCE SHEETS
Accounts receivable, allowance for doubtful accounts (in dollars)	$ 14		$ 14
Materials and supplies, allowance for obsolescence (in dollars)	$ 112		$ 109
Shares, CHF par value (in Swiss francs per share)		15.00		15.00
Shares, authorized	396,260,487	396,260,487	396,260,487	396,260,487
Shares, conditionally authorized	167,617,649	167,617,649
Shares, issued	373,830,649	373,830,649	373,830,649	373,830,649
Shares, outstanding	363,346,369	363,346,369	362,279,530	362,279,530
Treasury shares	2,863,267	2,863,267	2,863,267	2,863,267

- Definition

Amount of valuation reserve for inventory.

+ References+ Details

CONDENSED CONSOLIDATED STATEMENTS OF EQUITY (USD $) In Millions, unless otherwise specified	Total controlling interest shareholders' equity	Shares	Additional paid-in capital	Treasury shares, at cost	Retained earnings	Accumulated other comprehensive loss	Noncontrolling interest	Total
Balance at Dec. 31, 2013	$ 16,691	$ 5,147	$ 6,784	$ (240)	$ 5,262	$ (262)	$ (6)	$ 16,685
Balance (in shares) at Dec. 31, 2013		361
Increase (Decrease) in Shareholders' Equity
Total comprehensive income (loss)								465
Other comprehensive income (loss) attributable to controlling interest						(1)		(1)
Total comprehensive income (loss) attributable to controlling interest	455							455
Share-based compensation	28		28					28
Issuance of shares under share-based compensation plans	1	17	(16)					1
Issuance of shares under share-based compensation plans (in shares)		1
Total comprehensive income attributable to noncontrolling interest							10	(10)
Net income (loss) attributable to controlling interest					456			456
Other, net	(4)		(4)					(4)
Balance at Mar. 31, 2014	17,171	5,164	6,792	(240)	5,718	(263)	4	17,175
Balance (in shares) at Mar. 31, 2014		362
Balance at Dec. 31, 2014	13,671	5,169	5,797	(240)	3,349	(404)	311	13,982
Balance (in shares) at Dec. 31, 2014		362
Increase (Decrease) in Shareholders' Equity
Total comprehensive income (loss)								(479)
Other comprehensive income (loss) attributable to controlling interest						(10)		(10)
Total comprehensive income (loss) attributable to controlling interest	(493)							(493)
Share-based compensation	19		19					19
Issuance of shares under share-based compensation plans	(1)	14	(15)					(1)
Issuance of shares under share-based compensation plans (in shares)		1
Allocated capital for sale of noncontrolling interest	9		9				(9)
Distributions to holders of non controlling interest							(7)	(7)
Total comprehensive income attributable to noncontrolling interest							14	(14)
Net income (loss) attributable to controlling interest					(483)			(483)
Other, net	(4)		(4)					(4)
Balance at Mar. 31, 2015	$ 13,201	$ 5,183	$ 5,806	$ (240)	$ 2,866	$ (414)	$ 309	$ 13,510
Balance (in shares) at Mar. 31, 2015		363

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities
Net income (loss)	$ (469)	$ 466
Adjustments to reconcile to net cash provided by operating activities:
Amortization of drilling contract intangibles	(4)	(4)
Depreciation	291	273
Share-based compensation expense	19	28
Loss on impairment	936	65
Loss on disposal of assets, net	7	3
Loss on disposal of assets in discontinued operations, net		10
Deferred income taxes	(98)	(15)
Other, net	12	12
Changes in deferred revenue, net	(39)	(26)
Changes in deferred costs, net	57	38
Changes in operating assets and liabilities	(186)	(714)
Net cash provided by operating activities	526	136
Cash flows from investing activities
Capital expenditures	(201)	(1,131)
Proceeds from disposal of assets, net	7	91
Proceeds from disposal of assets in discontinued operations, net	2	14
Other, net		(12)
Net cash used in investing activities	(192)	(1,038)
Cash flows from financing activities
Repayments of debt	(63)	(237)
Proceeds from restricted cash investments	57	107
Deposits to restricted cash investments		(20)
Distribution of qualifying additional paid-in capital	(272)	(202)
Distribution to holders of noncontrolling interest	(7)
Other, net	(2)	(2)
Net cash used in financing activities	(287)	(354)
Net increase (decrease) in cash and cash equivalents	47	(1,256)
Cash and cash equivalents at beginning of period	2,635	3,243
Cash and cash equivalents at end of period	$ 2,682	$ 1,987

Business	3 Months Ended
Business	Mar. 31, 2015
Business
Business	Note 1—Business Transocean Ltd. (together with its subsidiaries and predecessors, unless the context requires otherwise, “Transocean,” the “Company,” “we,” “us” or “our”) is a leading international provider of offshore contract drilling services for oil and gas wells. We specialize in technically demanding sectors of the offshore drilling business with a particular focus on deepwater and harsh environment drilling services. Our mobile offshore drilling fleet is considered one of the most versatile fleets in the world. We contract our drilling rigs, related equipment and work crews predominantly on a dayrate basis to drill oil and gas wells. At March 31, 2015, we owned or had partial ownership interests in and operated 66 mobile offshore drilling units associated with our continuing operations. At March 31, 2015, our fleet consisted of 42 High-Specification Floaters (Ultra-Deepwater, Deepwater and Harsh Environment semisubmersibles and drillships), 14 Midwater Floaters, and 10 High-Specification Jackups. At March 31, 2015, we also had seven Ultra-Deepwater drillships and five High-Specification Jackups under construction or under contract to be constructed. See Note 9—Drilling Fleet. On August 5, 2014, we completed an initial public offering to sell a noncontrolling interest in Transocean Partners LLC (“Transocean Partners”), a Marshall Islands limited liability company, which was formed on February 6, 2014, by Transocean Partners Holdings Limited, a Cayman Islands company and our wholly owned subsidiary, to own, operate and acquire modern, technologically advanced offshore drilling rigs. See Note 15—Noncontrolling Interest.

Significant Accounting Policies	3 Months Ended
Significant Accounting Policies	Mar. 31, 2015
Significant Accounting Policies
Significant Accounting Policies	Note 2—Significant Accounting Policies Presentation—We have prepared our accompanying unaudited condensed consolidated financial statements in accordance with accounting principles generally accepted in the U.S. for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X of the U.S. Securities and Exchange Commission (“SEC”). Pursuant to such rules and regulations, these financial statements do not include all disclosures required by accounting principles generally accepted in the U.S. for complete financial statements. The condensed consolidated financial statements reflect all adjustments, which are, in the opinion of management, necessary for a fair presentation of financial position, results of operations and cash flows for the interim periods. Such adjustments are considered to be of a normal recurring nature unless otherwise noted. Operating results for the three months ended March 31, 2015 are not necessarily indicative of the results that may be expected for the year ending December 31, 2015 or for any future period. The accompanying condensed consolidated financial statements and notes thereto should be read in conjunction with the audited consolidated financial statements and notes thereto as of December 31, 2014 and 2013 and for each of the three years in the period ended December 31, 2014 included in our annual report on Form 10-K filed on February 26, 2015. Accounting estimates—To prepare financial statements in accordance with accounting principles generally accepted in the U.S., we are required to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses and the disclosures of contingent assets and liabilities. On an ongoing basis, we evaluate our estimates and assumptions, including those related to our allowance for doubtful accounts, materials and supplies obsolescence, assets held for sale, property and equipment, investments, income taxes, contingencies, share-based compensation, defined benefit pension plans and other postretirement benefits. We base our estimates and assumptions on historical experience and on various other factors we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying amounts of assets and liabilities that are not readily apparent from other sources. Actual results could differ from such estimates. Fair value measurements—We estimate fair value at a price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants in the principal market for the asset or liability. Our valuation techniques require inputs that we categorize using a three-level hierarchy, from highest to lowest level of observable inputs, as follows: (1) significant observable inputs, including unadjusted quoted prices for identical assets or liabilities in active markets (“Level 1”), (2) significant other observable inputs, including direct or indirect market data for similar assets or liabilities in active markets or identical assets or liabilities in less active markets (“Level 2”) and (3) significant unobservable inputs, including those that require considerable judgment for which there is little or no market data (“Level 3”). When multiple input levels are required for a valuation, we categorize the entire fair value measurement according to the lowest level of input that is significant to the measurement even though we may have also utilized significant inputs that are more readily observable. Consolidation—We consolidate entities in which we have a majority voting interest and entities that meet the criteria for variable interest entities for which we are deemed to be the primary beneficiary for accounting purposes. We eliminate intercompany transactions and accounts in consolidation. We apply the equity method of accounting for an investment in an entity if we have the ability to exercise significant influence over the entity that (a) does not meet the variable interest entity criteria or (b) meets the variable interest entity criteria, but for which we are not deemed to be the primary beneficiary. We apply the cost method of accounting for an investment in an entity if we do not have the ability to exercise significant influence over the unconsolidated entity. We separately present within equity on our condensed consolidated balance sheets the ownership interests attributable to parties with noncontrolling interests in our consolidated subsidiaries, and we separately present net income attributable to such parties on our condensed consolidated statements of operations. See Note 4—Variable Interest Entities and Note 15—Noncontrolling Interest. Property and equipment—The carrying amounts of our property and equipment, consisting primarily of offshore drilling rigs and related equipment, are based on our estimates, assumptions and judgments relative to capitalized costs, useful lives and salvage values of our rigs. These estimates, assumptions and judgments reflect both historical experience and expectations regarding future industry conditions and operations. At March 31, 2015, the aggregate carrying amount of our property and equipment represented approximately 76 percent of our total assets. We compute depreciation using the straight-line method after allowing for salvage values. In December 2014, we reduced the salvage values of certain drilling units due to existing market conditions. In the three months ended March 31, 2015, this change in estimate resulted in increased depreciation expense of $30 million ($28 million, or $0.08 per diluted share, net of tax). For the year ending December 31, 2015, we expect this change in estimate to result in increased depreciation expense of approximately $76 million ($73 million, net of tax). Share-based compensation—In the three months ended March 31, 2015 and 2014, we recognized share-based compensation expense of $19 million and $28 million, respectively. Capitalized interest—We capitalize interest costs for qualifying construction and upgrade projects. In the three months ended March 31, 2015 and 2014, we capitalized interest costs on construction work in progress of $26 million and $34 million, respectively. Reclassifications—We have made certain reclassifications to prior period amounts to conform with the current period’s presentation. Such reclassifications did not have a material effect on our condensed consolidated statement of financial position, results of operations or cash flows. Subsequent events—We evaluate subsequent events through the time of our filing on the date we issue our financial statements. See Note 18—Subsequent Events.

- Definition

The entire disclosure for all significant accounting policies of the reporting entity.

+ References+ Details

New Accounting Pronouncements	3 Months Ended
New Accounting Pronouncements	Mar. 31, 2015
New Accounting Pronouncements
New Accounting Pronouncements	Note 3—New Accounting Pronouncements Recently adopted accounting standards Presentation of financial statements—Effective January 1, 2015, we adopted the accounting standards update that changes the criteria for reporting discontinued operations. The update expands the disclosures for discontinued operations and requires new disclosures related to the disposal of individually significant components of an entity that do not qualify for discontinued operations. The update is effective for interim and annual periods beginning on or after December 15, 2014 and does not apply to components, such as our discontinued operations, that have been evaluated and reported as discontinued operations under previous guidance. Our adoption did not have an effect on our condensed consolidated financial statements or the disclosures contained in our notes to condensed consolidated financial statements. Recently issued accounting standards Interest—Effective January 1, 2016, we will adopt the accounting standards update that requires debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. The update is effective for interim and annual periods beginning after December 15, 2015. We do not expect that our adoption will have a material effect on our condensed consolidated balance sheets or the disclosures contained in our notes to condensed consolidated financial statements. Presentation of financial statements—Effective with our annual report for the period ending December 31, 2016, we will adopt the accounting standards update that requires us to evaluate whether there are conditions or events, considered in the aggregate, that raise substantial doubt about our ability to continue as a going concern within one year after the date that the financial statements are issued. The update is effective for the annual period ending after December 15, 2016 and for interim and annual periods thereafter. We do not expect that our adoption will have a material effect on the disclosures contained in our notes to condensed consolidated financial statements. Revenue from contracts with customers—Effective January 1, 2017, we will adopt the accounting standards update that requires an entity to recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The update is effective for interim and annual periods beginning on or after December 15, 2016. We are evaluating the requirements to determine the effect such requirements may have on our revenue recognition policies.

- Definition

The entire disclosure of changes in accounting principles, including adoption of new accounting pronouncements, that describes the new methods, amount and effects on financial statement line items.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 01

-Paragraph b

-Subparagraph 6

-Article 10

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 270

-SubTopic 10

-Section 45

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=6372559&loc=d3e765-108305

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 270

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=6372559&loc=d3e725-108305

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 250

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=28359718&loc=d3e22499-107794

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 250

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28359718&loc=d3e22580-107794

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Direct Effects of a Change in Accounting Principle

-URI http://asc.fasb.org/extlink&oid=6510796

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Indirect Effects of a Change in Accounting Principle

-URI http://asc.fasb.org/extlink&oid=6515603

Reference 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accounting Change

-URI http://asc.fasb.org/extlink&oid=6503790

Reference 9: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Change in Accounting Principle

-URI http://asc.fasb.org/extlink&oid=6507316

Reference 10: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 270

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.10-01.(b)(6))

-URI http://asc.fasb.org/extlink&oid=27015980&loc=d3e46468-122699

Reference 11: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Retrospective Application

-URI http://asc.fasb.org/extlink&oid=6523989

Reference 12: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 250

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=28359718&loc=d3e22583-107794

+ Details

Variable Interest Entities

3 Months Ended

Mar. 31, 2015

Variable Interest Entities

Variable Interest Entities

Note 4—Variable Interest Entities

Consolidated variable interest entities—Angola Deepwater Drilling Company Limited (“ADDCL”), a consolidated Cayman Islands company, and Transocean Drilling Services Offshore Inc. (“TDSOI”), a consolidated British Virgin Islands company, are variable interest entities for which we are the primary beneficiary. Accordingly, we consolidate the operating results, assets and liabilities of ADDCL and TDSOI. The carrying amounts associated with our consolidated variable interest entities, after eliminating the effect of intercompany transactions, were as follows (in millions):

	March 31, 2015		December 31, 2014
Assets	$	1,257	$	1,257
Liabilities	65		74
Net carrying amount	$	1,192	$	1,183

Impairments	3 Months Ended
Impairments	Mar. 31, 2015
Impairments
Impairments	Note 5—Impairments Assets held and used—During the three months ended March 31, 2015, we identified indicators that the asset groups in our contract drilling services reporting unit may not be recoverable. Such indicators included a reduction in the number of new contract opportunities, recent low dayrate fixtures and contract terminations. Our Deepwater Floater asset group, in particular, has seen further declines in projected dayrates and utilization partly caused by more technologically advanced drilling units aggressively competing with less capable drilling units. As a result of our testing, we determined that the carrying amount of the Deepwater Floater asset group was impaired. In the three months ended March 31, 2015, we recognized a loss of $507 million ($481 million, or $1.34 per diluted share, net of tax) associated with the impairment of these long-lived assets. We measured the fair value of the asset group by applying a combination of income and cost approaches, using projected discounted cash flows and estimates of the exchange price that would be received for the assets in the principal or most advantageous market for the assets in an orderly transaction between market participants as of the measurement date. Our estimate of fair value required us to use significant unobservable inputs, representative of a Level 3 fair value measurement, including assumptions related to the future performance of our contract drilling services reporting unit, such as future commodity prices, projected demand for our services, rig availability and dayrates. If we experience increasingly unfavorable changes to actual or anticipated dayrates or other impairment indicators, or if we are unable to secure new or extended contracts for our active units or the reactivation of any of our stacked units, we may be required to recognize additional losses in future periods as a result of impairments of the carrying amount of one or more of our asset groups. Assets held for sale—In the three months ended March 31, 2015, we recognized an aggregate loss of $429 million ($393 million, or $1.07 per diluted share, net of tax), associated with the impairment of the Ultra-Deepwater Floater Deepwater Expedition, the Deepwater Floaters Sedco 707 and Transocean Rather and the Midwater Floaters GSF Aleutian Key, GSF Arctic III and Transocean Legend, along with related equipment, which were classified as assets held for sale at the time of impairment. We measured the impairment of the drilling units and related equipment as the amount by which the carrying amount exceeded the estimated fair value less costs to sell. We estimated the fair value of the assets using significant other observable inputs, representative of Level 2 fair value measurements, including indicative market values for the drilling units and related equipment to be sold for scrap value. In the three months ended March 31, 2014, we recognized an aggregate loss of $65 million ($0.19 per diluted share), which had no tax effect, associated with the impairment of the Midwater Floater Sedneth 701 and the High-Specification Jackup GSF Magellan, along with related equipment, which were classified as assets held for sale at the time of impairment. We measured the impairments of the drilling units and related equipment as the amount by which the carrying amount exceeded the estimated fair value less costs to sell. We estimated the fair value of the assets using significant other observable inputs, representative of Level 2 fair value measurements, including indicative market values for comparable drilling units or a binding sale and purchase agreement for the drilling units and related equipment. If we commit to plans to sell additional rigs for scrap value, we may be required to recognize additional losses in future periods associated with the impairment of such assets. See Note 18—Subsequent Events.

Income Taxes

3 Months Ended

Mar. 31, 2015

Income Taxes

Income Taxes

Note 6—Income Taxes

Tax rate—Transocean Ltd., a holding company and Swiss resident, is exempt from cantonal and communal income tax in Switzerland, but is subject to Swiss federal income tax. At the federal level, qualifying net dividend income and net capital gains on the sale of qualifying investments in subsidiaries are exempt from Swiss federal income tax. Consequently, Transocean Ltd. expects dividends from its subsidiaries and capital gains from sales of investments in its subsidiaries to be exempt from Swiss federal income tax.

Our provision for income taxes is based on the tax laws and rates applicable in the jurisdictions in which we operate and earn income. The relationship between our provision for or benefit from income taxes and our income or loss before income taxes can vary significantly from period to period considering, among other factors, (a) the overall level of income before income taxes, (b) changes in the blend of income that is taxed based on gross revenues rather than income before taxes, (c) rig movements between taxing jurisdictions and (d) our rig operating structures. Generally, our annual marginal tax rate is lower than our annual effective tax rate. In the three months ended March 31, 2015 and 2014, our estimated annual effective tax rates were 25.8 percent and 15.1 percent, respectively, based on estimated annual income from continuing operations before income taxes, after excluding certain items, such as losses on impairment and gains and losses on certain asset disposals. The tax effect, if any, of the excluded items as well as settlements of prior year tax liabilities and changes in prior year tax estimates are all treated as discrete period tax expenses or benefits.

In December 2014, the U.K. Treasury released a draft proposal that would impose tax on groups that use certain tax planning techniques that are perceived as diverting profits from the U.K. The Diverted Profit Tax rule was included in the 2015 Finance Bill and on March 26, 2015, the legislation received Royal Assent with an effective date of April 1, 2015. The change in the law did not affect our existing annual income tax rate or deferred tax balances.

Deferred taxes—The valuation allowance for our non-current deferred tax assets was as follows (in millions):

		March 31, 2015			December 31, 2014
Valuation allowance for non-current deferred tax assets		$	395		$	340

The increase in the valuation allowance for our non-current deferred tax assets was primarily related to the current net operating losses generated in Norway and the U.K. carryforward deductions related to charter payments.

Unrecognized tax benefits—The liabilities related to our unrecognized tax benefits, including related interest and penalties that we recognize as a component of income tax expense, were as follows (in millions):

	March 31, 2015		December 31, 2014
Unrecognized tax benefits, excluding interest and penalties	$	271	$	265
Interest and penalties	120		120
Unrecognized tax benefits, including interest and penalties	$	391	$	385

In the year ending December 31, 2015, it is reasonably possible that our existing liabilities for unrecognized tax benefits may increase or decrease primarily due to the progression of open audits or the expiration of statutes of limitation. However, we cannot reasonably estimate a range of potential changes in our existing liabilities for unrecognized tax benefits due to various uncertainties, such as the unresolved nature of various audits.

Tax returns—We file federal and local tax returns in several jurisdictions throughout the world. With few exceptions, we are no longer subject to examinations of our U.S. and non-U.S. tax matters for years prior to 2010.

Our tax returns in the major jurisdictions in which we operate, other than the U.S., Norway and Brazil, which are mentioned below, are generally subject to examination for periods ranging from three to six years. We have agreed to extensions beyond the statute of limitations in two major jurisdictions for up to 20 years. Tax authorities in certain jurisdictions are examining our tax returns and in some cases have issued assessments. We are defending our tax positions in those jurisdictions. While we cannot predict or provide assurance as to the timing or the outcome of these proceedings, we do not expect the ultimate liability to have a material adverse effect on our consolidated statement of financial position or results of operations, although it may have a material adverse effect on our consolidated statement of cash flows.

U.S. tax investigations—In January 2014, we received a draft assessment from the U.S. tax authorities related to our 2010 and 2011 U.S. federal income tax returns. The significant issue raised in the assessment relates to transfer pricing for certain charters of drilling rigs between our subsidiaries. This issue, if successfully challenged, would result in net adjustments of approximately $290 million of additional taxes, excluding interest and penalties. We believe our U.S. federal income tax returns are materially correct as filed, and we intend to continue to vigorously defend against all such claims to the contrary. An unfavorable outcome on these adjustments could result in a material adverse effect on our consolidated statement of financial position, results of operations or cash flows. Furthermore, if the authorities were to continue to pursue these positions with respect to subsequent years and were successful in such assertions, our effective tax rate on worldwide earnings with respect to years following 2011 could increase substantially, and could have a material adverse effect on our consolidated results of operations or cash flows.

Norway tax investigations and trial—Norwegian civil tax and criminal authorities are investigating various transactions undertaken by our subsidiaries in 1999, 2001 and 2002 as well as the actions of certain employees of our former external tax advisors on these transactions. The authorities issued tax assessments as follows: (a) NOK 684 million, equivalent to approximately $85 million, plus interest, related to the migration of our subsidiary that was previously subject to tax in Norway, (b) NOK 412 million, equivalent to approximately $51 million, plus interest, related to a 2001 dividend payment and (c) NOK 43 million, equivalent to approximately $5 million, plus interest, related to certain foreign exchange deductions and dividend withholding tax. In November 2012, the Norwegian district court in Oslo heard the civil tax case regarding the disputed tax assessment of NOK 684 million related to the migration of our subsidiary. On March 1, 2013, the Norwegian district court in Oslo overturned the initial civil tax assessment and ruled in our favor, and the tax authorities filed an appeal. On June 26, 2014, the Norwegian district court in Oslo ruled that our subsidiary was liable for the civil tax assessment of NOK 412 million, equivalent to approximately $51 million, but waived all penalties and interest. On September 12, 2014, we filed an appeal. We intend to take all other appropriate action to continue to support our position that our Norwegian tax returns are materially correct as filed.

In June 2011, the Norwegian authorities issued criminal indictments against two of our subsidiaries alleging misleading or incomplete disclosures in Norwegian tax returns for the years 1999 through 2002, as well as inaccuracies in Norwegian statutory financial statements for the years ended December 31, 1996 through 2001. Two employees of our former external tax advisors were also issued criminal indictments with respect to the disclosures in our tax returns, and our former external Norwegian tax attorney was issued criminal indictments related to certain of our restructuring transactions and the 2001 dividend payment. In January 2012, the Norwegian authorities supplemented the previously issued criminal indictments by issuing a financial claim of NOK 1.8 billion, equivalent to approximately $223 million, jointly and severally, against our two subsidiaries, the two external tax advisors and the external tax attorney. In February 2012, the authorities dropped the previously existing civil tax claim related to a certain restructuring transaction. In April 2012, the Norwegian tax authorities supplemented the previously issued criminal indictments against our two subsidiaries by extending a criminal indictment against a third subsidiary, alleging misleading or incomplete disclosures in Norwegian tax returns for the years 2001 and 2002. The criminal trial commenced in December 2012. In May 2013, the Norwegian authorities dropped the financial claim of NOK 1.8 billion against one of our subsidiaries and the criminal case related to the migration case of another subsidiary. The criminal trial proceedings ended in September 2013. The Norwegian authorities subsequently suggested, if we were found guilty, that the court assess criminal penalties of NOK 230 million, equivalent to approximately $29 million, against three of our subsidiaries in addition to any civil tax penalties and the financial claim.

On July 2, 2014, the Norwegian district court in Oslo acquitted our three subsidiaries, two external tax attorneys and an external tax advisor of all criminal charges related to the disclosures in our Norwegian tax returns for the years 1999 through 2002 and statutory financial statements for the years ended December 31, 1996 through 2001. On July 16, 2014, the Norwegian authorities dropped the financial claim of NOK 1.8 billion, equivalent to approximately $223 million, against two of our subsidiaries, fully closing this matter, and on the same date, filed an appeal with respect to the following charges: (a) disclosures in our Norwegian tax returns related to a dividend payment in 2001, (b) disclosures in our Norwegian tax returns related to an intercompany rig sale in 1999 and (c) certain inaccuracies in Norwegian statutory financial statements for the years ended December 31, 1996 through 2001. We believe our Norwegian tax returns are materially correct as filed, and we intend to continue to vigorously contest any assertions to the contrary by the Norwegian civil and criminal authorities in connection with the various transactions being investigated. An unfavorable outcome on the Norwegian civil or criminal tax matters could result in a material adverse effect on our consolidated statement of financial position, results of operations or cash flows.

Brazil tax investigations—Certain of our Brazilian income tax returns for the years 2000 through 2004 are currently under examination. In December 2005, the Brazilian tax authorities issued an aggregate tax assessment of BRL 723 million, equivalent to approximately $226 million, including a 75 percent penalty and interest. On January 25, 2008, we filed a protest letter with the Brazilian tax authorities, and we are currently engaged in the appeals process. On May 19, 2014, with respect to our Brazilian income tax returns for the years 2009 and 2010, the Brazilian tax authorities issued an aggregate tax assessment of BRL 126 million, equivalent to approximately $39 million, including a 75 percent penalty and interest. On June 18, 2014, we filed a protest letter with the Brazilian tax authorities. We believe our returns are materially correct as filed, and we are vigorously contesting these assessments. An unfavorable outcome on these proposed assessments could result in a material adverse effect on our consolidated statement of financial position, results of operations or cash flows.

Other tax matters—We conduct operations through our various subsidiaries in a number of countries throughout the world. Each country has its own tax regimes with varying nominal rates, deductions, employee contribution requirements and tax attributes. From time to time, we may identify changes to previously evaluated tax positions that could result in adjustments to our recorded assets and liabilities. Although we are unable to predict the outcome of these changes, we do not expect the effect, if any, resulting from these adjustments to have a material adverse effect on our consolidated statement of financial position, results of operations or cash flows.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References+ Details

Discontinued Operations

3 Months Ended

Mar. 31, 2015

Discontinued Operations

Discontinued Operations

Note 7—Discontinued Operations

Summarized results of discontinued operations

The summarized results of operations included in income from discontinued operations were as follows (in millions):

	Three months ended March 31,
	2015			2014
Operating revenues	$	—		$	108
Operating and maintenance expense	(1		)	(104		)
Loss on disposal of assets in discontinued operations, net	—			(10		)
Loss from discontinued operations before income tax expense	(1		)	(6		)
Income tax expense	(1		)	(2		)
Loss from discontinued operations, net of tax	$	(2	)	$	(8	)

Standard jackup and swamp barge contract drilling services

Overview—In September 2012, in connection with our efforts to dispose of non-strategic assets and to reduce our exposure to low-specification drilling units, we committed to a plan to discontinue operations associated with the standard jackup and swamp barge asset groups, components of our contract drilling services operating segment.

Sale transactions with Shelf Drilling—In November 2012, we completed the sale of 38 drilling units to Shelf Drilling Holdings, Ltd. (“Shelf Drilling”). For a transition period following the completion of the sale transactions, we agreed to continue to operate a substantial portion of the standard jackups under operating agreements with Shelf Drilling and to provide certain other transition services to Shelf Drilling. Under the operating agreements, we agreed to remit the collections from our customers under the associated drilling contracts to Shelf Drilling, and Shelf Drilling agreed to reimburse us for our direct costs and expenses incurred while operating the standard jackups on behalf of Shelf Drilling with certain exceptions. Amounts due to Shelf Drilling under the operating agreements and transition services agreement may be contractually offset against amounts due from Shelf Drilling. The costs to us for providing such operating and transition services, including allocated indirect costs, have exceeded the amounts we receive from Shelf Drilling for providing such services.

Under the operating agreements, we agreed to continue to operate these standard jackups on behalf of Shelf Drilling for periods ranging from nine months to 27 months, until expiration or novation of the underlying drilling contracts by Shelf Drilling. As of March 31, 2015, we no longer operated drilling units for Shelf Drilling. Until the expiration or novation of such drilling contracts, we retained possession of the materials and supplies associated with the standard jackups that we operated under the operating agreements. In the three months ended March 31, 2015 and 2014, we received cash proceeds of $2 million and $3 million, respectively, associated with the sale of equipment and materials and supplies to Shelf Drilling upon expiration or novation of the drilling contracts. Under a transition services agreement, we provided certain transition services through May 2014.

For a period through November 2015, we agreed to provide to Shelf Drilling up to $125 million of financial support by maintaining letters of credit, surety bonds and guarantees for various contract bidding and performance activities associated with the drilling units sold to Shelf Drilling and in effect at the closing of the sale transactions. At the time of the sale transactions, we had $113 million of outstanding letters of credit, issued under our committed and uncommitted credit lines, in support of rigs sold to Shelf Drilling. Included within the $125 million maximum amount, we agreed to provide up to $65 million of additional financial support in connection with any new drilling contracts related to such drilling units. Shelf Drilling is required to reimburse us in the event that any of these instruments are called. At March 31, 2015 and December 31, 2014, we had $79 million and $91 million, respectively, of outstanding letters of credit, issued under our committed and uncommitted credit lines, in support of drilling units sold to Shelf Drilling. See Note 13—Commitments and Contingencies.

Other dispositions—During the three months ended March 31, 2014, we recognized a net gain of $1 million, which had no tax effect, related to the disposal of assets unrelated to rig sales.

Drilling management services

Overview—In February 2014, in connection with our efforts to discontinue non-strategic operations, we completed the sale of ADTI, which performs drilling management services in the North Sea. As a result of the sale, we reclassified the results of operations of our drilling management services operating segment to discontinued operations for all periods presented.

Disposition—In the three months ended March 31, 2014, we received net cash proceeds of $11 million and recognized a net loss of $11 million ($0.03 per diluted share), which had no tax effect, associated with the sale of the drilling management services business. We also agreed to provide a $15 million working capital line of credit to the buyer through March 2016. We earn interest on the outstanding borrowings at a fixed rate of 8.3 percent per annum, payable quarterly. At March 31, 2015 and December 31, 2014, ADTI had borrowings of $15 million outstanding under the working capital line of credit, recorded in other assets.

- Definition

The entire disclosure for the facts and circumstances leading to the completed or expected disposal, manner and timing of disposal, the gain (loss) recognized in the income statement and the income statement caption that includes that gain (loss), amounts of revenues and pretax profit or loss reported in discontinued operations, the segment in which the disposal group was reported, and the classification (whether sold or classified as held for sale) and carrying value of the assets and liabilities comprising the disposal group. Includes all disposal groups, including those classified as components of the entity (discontinued operations).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2941-110230

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e957-107759

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1012-107759

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1510-107760

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1020-107759

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=8077374&loc=d3e2443-110228

Reference 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1474-107760

Reference 9: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1436-107760

+ Details

Earnings (Loss) Per Share

3 Months Ended

Mar. 31, 2015

Earnings (Loss) Per Share

Earnings (Loss) Per Share

Note 8—Earnings (Loss) Per Share

The numerator and denominator used for the computation of basic and diluted per share earnings (loss) from continuing operations were as follows (in millions, except per share data):

	Three months ended March 31,
	2015						2014
	Basic			Diluted			Basic			Diluted
Numerator for earnings (loss) per share
Income (loss) from continuing operations attributable to controlling interest	$	(481	)	$	(481	)	$	464		$	464
Undistributed earnings allocable to participating securities	—			—			(4		)	(4		)
Income (loss) from continuing operations available to shareholders	$	(481	)	$	(481	)	$	460		$	460

Denominator for earnings (loss) per share
Weighted-average shares outstanding	363			363			361			361
Effect of stock options and other share-based awards	—			—			—			—
Weighted-average shares for per share calculation	363			363			361			361

Per share earnings (loss) from continuing operations	$	(1.32	)	$	(1.32	)	$	1.27		$	1.27

In the three months ended March 31, 2015 and 2014, we excluded 5.0 million and 2.3 million share-based awards, respectively, from the calculation since the effect would have been anti-dilutive.

- Definition

The entire disclosure for earnings per share.

+ References+ Details

Drilling Fleet

3 Months Ended

Mar. 31, 2015

Drilling Fleet

Drilling Fleet

Note 9—Drilling Fleet

Construction work in progress—For the three months ended March 31, 2015 and 2014, the changes in our construction work in progress, including capital expenditures and capitalized interest, were as follows (in millions):

	Three months ended March 31,
	2015			2014
Construction work in progress, at beginning of period	$	2,451		$	2,710

Newbuild construction program
Deepwater Invictus (a) (b)	—			442
Deepwater Asgard (a) (b)	—			230
Deepwater Thalassa (c)	25			32
Deepwater Proteus (c)	9			6
Deepwater Conqueror (d)	18			80
Deepwater Pontus (c)	18			79
Deepwater Poseidon (c)	6			24
Ultra-Deepwater drillship TBN1 (e)	2			27
Transocean Cassiopeia (f)	1			1
Ultra-Deepwater drillship TBN2 (e)	—			27
Transocean Centaurus (f)	1			1
Transocean Cepheus (f)	1			1
Transocean Cetus (f)	1			1
Transocean Circinus (f)	1			1
Other construction projects and capital additions	118			179
Total capital expenditures	201			1,131
Changes in accrued capital expenditures	(22		)	(48		)

Property and equipment placed into service
Other property and equipment	(91		)	(178		)
Construction work in progress, at end of period	$	2,539		$	3,615

(a)

The accumulated construction costs of this rig are no longer included in construction work in progress, as the construction project had been completed as of March 31, 2015.

(b)

The Ultra-Deepwater drillships Deepwater Invictus and Deepwater Asgard, commenced operations in July 2014 and August 2014, respectively. The total carrying amount included capitalized costs of $272 million, representing the estimated fair value of construction in progress acquired in connection with our acquisition of Aker Drilling ASA in October 2011.

(c)

Deepwater Thalassa, Deepwater Proteus, Deepwater Pontus and Deepwater Poseidon, four newbuild Ultra-Deepwater drillships under construction at the Daewoo Shipbuilding & Marine Engineering Co. Ltd. shipyard in Korea, are expected to commence operations in the first quarter of 2016, the third quarter of 2016, the first quarter of 2017 and the second quarter of 2017, respectively.

(d)

Deepwater Conqueror, a newbuild Ultra-Deepwater drillship under construction at the Daewoo Shipbuilding & Marine Engineering Co. Ltd. shipyard in Korea, is expected to commence operations in the fourth quarter of 2016.

(e)

Our two unnamed dynamically positioned Ultra-Deepwater drillships under construction at the Jurong Shipyard PTE Ltd. in Singapore do not yet have drilling contracts and are expected to be delivered in the second quarter of 2017 and the first quarter of 2018, respectively.

(f)

Transocean Cassiopeia, Transocean Centaurus, Transocean Cepheus, Transocean Cetus and Transocean Circinus, five Keppel FELS Super B 400 Bigfoot class design newbuild High-Specification Jackups under construction at Keppel FELS’ shipyard in Singapore do not yet have drilling contracts and are expected to be delivered in the first quarter of 2018, the third quarter of 2018, the first quarter of 2019, the third quarter of 2019 and the first quarter of 2020, respectively. These delivery expectations reflect our decision to delay delivery in consideration of existing market conditions.

Dispositions—During the three months ended March 31, 2015, in connection with our efforts to dispose of non-strategic assets, we completed the sale of the Deepwater Floater Discoverer Seven Seas and the Midwater Floater C. Kirk Rhein, Jr. along with related equipment, and in the three months ended March 31, 2015, we received aggregate net cash proceeds of $5 million. During the three months ended March 31, 2014, in connection with our efforts to dispose of non-strategic assets, we completed the sale of the High-Specification Jackup GSF Monitor along with related equipment, and in the three months ended March 31, 2014, we received net cash proceeds of $83 million. In the three months ended March 31, 2015 and 2014, we received cash proceeds of $2 million and $8 million, respectively, and recognized an aggregate net loss of $9 million and $3 million, respectively, associated with the disposal of certain corporate assets and unrelated rig equipment.

During the three months ended March 31, 2015, we committed to a plan to sell the Ultra-Deepwater Floater Deepwater Expedition, the Deepwater Floaters Sedco 707 and Transocean Rather and the Midwater Floaters GSF Aleutian Key, GSF Arctic III and Transocean Legend, along with related equipment. At March 31, 2015, the aggregate carrying amount of our assets held for sale was $23 million, including the Ultra-Deepwater Floater Deepwater Expedition, the Deepwater Floaters Sedco 707, Sedco 710, Sovereign Explorer and Transocean Rather and the Midwater Floaters Falcon 100, GSF Aleutian Key, GSF Arctic I, GSF Arctic III, J.W. McLean, Sedco 601, Sedco 700, Sedneth 701 and Transocean Legend, along with related equipment. At December 31, 2014, the aggregate carrying amount of our assets held for sale was $25 million, including an aggregate carrying amount of $23 million for the Deepwater Floaters Discoverer Seven Seas, Sedco 710 and Sovereign Explorer and the Midwater Floaters C. Kirk Rhein, Jr., Falcon 100, GSF Arctic I, J.W. McLean, Sedco 601, Sedco 700 and Sedneth 701, along with related equipment, and an aggregate carrying amount of $2 million for the then remaining assets of our discontinued operations.

See Note 5—Impairments, Note 7—Discontinued Operations and Note 18—Subsequent Events.

- Definition

The entire disclosure for long-lived, physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, accounting policies and methodology, roll forwards, depreciation, depletion and amortization expense, including composite depreciation, accumulated depreciation, depletion and amortization expense, useful lives and method used, income statement disclosures, assets held for sale and public utility disclosures.

+ References+ Details

Debt

3 Months Ended

Mar. 31, 2015

Debt

Debt

Note 10—Debt

Debt, net of unamortized discounts, premiums and fair value adjustments, was comprised of the following (in millions):

	March 31, 2015		December 31, 2014
4.95% Senior Notes due November 2015 (a)	$	896	$	898
5.05% Senior Notes due December 2016 (a)	1,000		999
2.5% Senior Notes due October 2017 (a)	749		748
Eksportfinans Loans due January 2018	288		369
6.00% Senior Notes due March 2018 (a)	1,004		1,001
7.375% Senior Notes due April 2018 (a)	247		247
6.50% Senior Notes due November 2020 (a)	921		911
6.375% Senior Notes due December 2021 (a)	1,199		1,199
3.8% Senior Notes due October 2022 (a)	746		745
7.45% Notes due April 2027 (a)	97		97
8% Debentures due April 2027 (a)	57		57
7% Notes due June 2028	309		309
Capital lease contract due August 2029	609		615
7.5% Notes due April 2031 (a)	599		598
6.80% Senior Notes due March 2038 (a)	999		999
7.35% Senior Notes due December 2041 (a)	300		300
Total debt	10,020		10,092
Less debt due within one year
4.95% Senior Notes due November 2015 (a)	896		898
Eksportfinans Loans due January 2018	106		114
Capital lease contract due August 2029	22		21
Total debt due within one year	1,024		1,033
Total long-term debt	$	8,996	$	9,059

(a)

Transocean Inc., a 100 percent owned subsidiary of Transocean Ltd., is the issuer of the notes and debentures, which have been guaranteed by Transocean Ltd. Transocean Ltd. has also guaranteed borrowings under the Five-Year Revolving Credit Facility. Transocean Ltd. and Transocean Inc. are not subject to any significant restrictions on their ability to obtain funds from their consolidated subsidiaries by dividends, loans or return of capital distributions. See Note 17—Condensed Consolidating Financial Information.

Scheduled maturities—At March 31, 2015, the scheduled maturities of our debt were as follows (in millions):

Twelve months ending March 31,
2016	$	1,022
2017	1,131
2018	1,858
2019	277
2020	33
Thereafter	5,675
Total debt, excluding unamortized discounts, premiums and fair value adjustments	9,996
Total unamortized discounts, premiums and fair value adjustments, net	24
Total debt	$	10,020

Five-Year Revolving Credit Facility—In June 2014, we entered into an amended and restated bank credit agreement, which established a $3.0 billion unsecured five-year revolving credit facility, that is scheduled to expire on June 28, 2019 (the “Five-Year Revolving Credit Facility”). Among other things, the Five-Year Revolving Credit Facility includes limitations on creating liens, incurring subsidiary debt, transactions with affiliates, sale/leaseback transactions, mergers and the sale of substantially all assets. The Five-Year Revolving Credit Facility also includes a covenant imposing a maximum debt to tangible capitalization ratio of 0.6 to 1.0. Borrowings under the Five-Year Revolving Credit Facility are subject to acceleration upon the occurrence of an event of default, borrowings are guaranteed by Transocean Ltd. and may be prepaid in whole or in part without premium or penalty.

We may borrow under the Five-Year Revolving Credit Facility at either (1) the adjusted London Interbank Offered Rate (“LIBOR”) plus a margin (the “Five-Year Revolving Credit Facility Margin”), which ranges from 1.125 percent to 2.0 percent based on the credit rating of our non-credit enhanced senior unsecured long-term debt (“Debt Rating”), or (2) the base rate specified in the credit agreement plus the Five-Year Revolving Credit Facility Margin, less one percent per annum. Throughout the term of the Five-Year Revolving Credit Facility, we pay a facility fee on the daily unused amount of the underlying commitment which ranges from 0.15 percent to 0.35 percent depending on our Debt Rating. In the three months ended March 31, 2015, our Debt Rating was reduced, and as a result, effective March 19, 2015, the Five-Year Revolving Credit Facility Margin increased to 1.75 percent from 1.5 percent and the facility fee increased to 0.275 percent from 0.225 percent. At March 31, 2015, we had no borrowings outstanding or letters of credit issued, and we had $3.0 billion of available borrowing capacity under the Five-Year Revolving Credit Facility.

5.05% Senior Notes, 6.375% Senior Notes and 7.35% Senior Notes—In December 2011, we issued $1.0 billion aggregate principal amount of 5.05% Senior Notes due December 2016 (the “5.05% Senior Notes”), $1.2 billion aggregate principal amount of 6.375% Senior Notes due December 2021 (the “6.375% Senior Notes”) and $300 million aggregate principal amount of 7.35% Senior Notes due December 2041 (the “7.35% Senior Notes”). The interest rates for the notes are subject to adjustment from time to time upon a change to our Debt Rating. In the three months ended March 31, 2015, our Debt Rating was reduced and, as a result, effective June 15, 2015, the interest rates on the 5.05% Senior Notes, the 6.375% Senior Notes and the 7.35% Senior Notes will increase 0.5 percent from the stated rate to 5.55 percent, 6.875 percent and 7.85 percent, respectively. At March 31, 2015, the aggregate outstanding principal amount of the 5.05% Senior Notes, the 6.375% Senior Notes and the 7.35% Senior Notes was $1.0 billion, $1.2 billion and $300 million, respectively.

2.5% Senior Notes and 3.8% Senior Notes—In September 2012, we issued $750 million aggregate principal amount of 2.5% Senior Notes due October 2017 (the “2.5% Senior Notes”) and $750 million aggregate principal amount of 3.8% Senior Notes due October 2022 (the “3.8% Senior Notes”). The interest rates for the notes are subject to adjustment from time to time upon a change to our Debt Rating. In the three months ended March 31, 2015, our Debt Rating was reduced and, as a result, effective April 15, 2015, the interest rates on the 2.5% Senior Notes and the 3.8% Senior Notes will increase 0.5 percent from the stated rate to 3.0 percent and 4.3 percent, respectively. At March 31, 2015, the aggregate outstanding principal amount of the 2.5% Senior Notes and the 3.8% Senior Notes was $750 million each.

Eksportfinans Loans—We have borrowings under the Loan Agreement dated September 12, 2008 and the Loan Agreement dated November 18, 2008, between one of our subsidiaries and Eksportfinans ASA (together, the “Eksportfinans Loans”). At March 31, 2015 and December 31, 2014, aggregate borrowings of NOK 2.3 billion and NOK 2.8 billion, respectively, equivalent to approximately $290 million and $370 million, respectively, were outstanding under the Eksportfinans Loans.

The Eksportfinans Loans require collateral to be held by a financial institution through expiration (the “Aker Restricted Cash Investments”). At March 31, 2015 and December 31, 2014, the aggregate principal amount of the Aker Restricted Cash Investments was NOK 2.3 billion and NOK 2.8 billion, respectively, equivalent to approximately $290 million and $370 million, respectively.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References+ Details

Derivatives and Hedging

3 Months Ended

Mar. 31, 2015

Derivatives and Hedging

Derivatives and Hedging

Note 11—Derivatives and Hedging

In March and April 2014, we entered into interest rate swaps, which are designated and qualify as a fair value hedge, to reduce our exposure to changes in the fair value of the 6.0% Senior Notes due March 2018 and the 6.5% Senior Notes due November 2020, respectively. The interest rate swaps have aggregate notional amounts equal to the corresponding face values of the hedged instruments and have stated maturities that coincide with those of the hedged instruments. We have determined that the hedging relationships qualify for and we have applied the shortcut method of accounting, under which the interest rate swaps are considered to have no ineffectiveness and no ongoing assessment of effectiveness is required. Accordingly, changes in the fair value of the interest rate swaps recognized in interest expense offset the changes in the fair value of the hedged fixed-rate notes.

At March 31, 2015, the aggregate notional amounts and the weighted average interest rates associated with our derivatives designated as hedging instruments were as follows (in millions, except weighted average interest rates):

	Pay					Receive
	Aggregate notional amount		Fixed or variable rate	Weighted average rate		Aggregate notional amount		Fixed or variable rate	Weighted average rate
Interest rate swaps, fair value hedge	$	1,500	Variable	4.69	%	$	1,500	Fixed	6.25	%

The balance sheet classification and aggregate carrying amount of our derivatives designated as hedging instruments, measured at fair value, were as follows (in millions):

		March 31,		December 31,
	Balance sheet classification	2015		2014
Interest rate swaps, fair value hedges	Other current assets	$	6	$	4
Interest rate swaps, fair value hedges	Other assets	27		11

- Definition

The entire disclosure for derivative instruments and hedging activities including, but not limited to, risk management strategies, non-hedging derivative instruments, assets, liabilities, revenue and expenses, and methodologies and assumptions used in determining the amounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4K

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5708775-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(n))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4J

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5708773-113959

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 25

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41635-113959

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624258-113959

Reference 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4A

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5618551-113959

Reference 9: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6441202&loc=d3e80720-113993

Reference 10: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=7668309&loc=d3e80748-113994

Reference 11: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4E

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624181-113959

Reference 12: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=7668309&loc=d3e80784-113994

Reference 13: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41620-113959

Reference 14: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4D

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624177-113959

Reference 15: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959

Reference 16: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959

Reference 17: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579240-113959

Reference 18: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41641-113959

Reference 19: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41638-113959

Reference 20: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959

+ Details

Postemployment Benefit Plans

3 Months Ended

Mar. 31, 2015

Postemployment Benefit Plans

Postemployment Benefit Plans

Note 12—Postemployment Benefit Plans

Defined benefit pension plans and other postretirement employee benefit plans

Effective January 1, 2015, we froze benefits of our qualified defined benefit pension plan in the U.S., which covers substantially all U.S. employees, and one of our unfunded supplemental benefit plans. Including these plans, we have several frozen defined benefit pension plans, both funded and unfunded, that cover certain current and former U.S. employees and certain former directors of our predecessors (the “U.S. Plans”). We also have various defined benefit plans in the U.K., Norway, Nigeria, Egypt and Indonesia that cover certain current and former employees in those areas (the “Non-U.S. Plans”). Additionally, we maintain several unfunded contributory and noncontributory other postretirement employee benefit plans covering substantially all of our U.S. employees (the “OPEB Plans”).

The components of net periodic benefit costs, before tax, and funding contributions for these plans were as follows (in millions):

	Three months ended March 31, 2015											Three months ended March 31, 2014
	U.S. Plans			Non-U.S. Plans			OPEB Plans		Total			U.S. Plans			Non-U.S. Plans			OPEB Plans		Total
Net periodic benefit costs
Service cost	$	1		$	7		$	—	$	8		$	11		$	8		$	—	$	19
Interest cost	16			5			1		22			17			6			1		24
Expected return on plan assets	(22		)	(6		)	—		(28		)	(19		)	(7		)	—		(26		)
Actuarial losses, net	3			2			—		5			5			1			—		6
Net periodic benefit costs	$	(2	)	$	8		$	1	$	7		$	14		$	8		$	1	$	23

Funding contributions	$	—		$	9		$	2	$	11		$	1		$	9		$	—	$	10

Commitments and Contingencies	3 Months Ended
Commitments and Contingencies	Mar. 31, 2015
Commitments and Contingencies
Commitments and Contingencies	Note 13—Commitments and Contingencies Macondo well incident settlement obligations On April 22, 2010, the Ultra-Deepwater Floater Deepwater Horizon sank after a blowout of the Macondo well caused a fire and explosion on the rig. Eleven persons were declared dead and others were injured as a result of the incident. At the time of the explosion, Deepwater Horizon was located approximately 41 miles off the coast of Louisiana in Mississippi Canyon Block 252 and was contracted to an affiliate of BP plc (together with its affiliates, “BP”). On January 3, 2013, we reached an agreement with the U.S. Department of Justice (“DOJ”) to resolve certain outstanding civil and potential criminal charges against us arising from the Macondo well incident. As part of this resolution, we agreed to a guilty plea (“Plea Agreement”) and a civil consent decree (“Consent Decree”) by which, among other things, we agreed to pay $1.4 billion in fines, recoveries and civil penalties, excluding interest, in scheduled payments through February 2017. In the three months ended March 31, 2015 and 2014, we paid an aggregate installment of $264 million and $472 million, respectively, including interest, towards our obligations under the Plea Agreement and Consent Decree. Macondo well incident contingencies Overview—We have recognized a liability for estimated loss contingencies associated with litigation and investigations resulting from the incident that we believe are probable and for which a reasonable estimate can be made. At March 31, 2015 and December 31, 2014, the liability for estimated loss contingencies that we believe are probable and for which a reasonable estimate can be made was $426 million, recorded in other current liabilities. The litigation and investigations also give rise to certain loss contingencies that we believe are either reasonably possible or probable but for which we do not believe a reasonable estimate can be made. Although we have not recognized a liability for such loss contingencies, these contingencies could result in liabilities that we ultimately recognize. We have also recognized an asset associated with the portion of our estimated losses, primarily related to the personal injury and fatality claims of our crew and vendors, that we believe is probable of recovery from insurance. At March 31, 2015 and December 31, 2014, the insurance recoverable asset was $10 million, recorded in other assets. Although we have available policy limits that could result in additional amounts recoverable from insurance, recovery of such additional amounts is not probable and we are not currently able to estimate such amounts (see “—Insurance coverage”). Our estimates involve a significant amount of judgment. As a result of new information or future developments, we may increase our estimated loss contingencies arising out of the Macondo well incident or reduce our estimated recoveries from insurance, and the resulting losses could have a material adverse effect on our consolidated statement of financial position, results of operations or cash flows. Multidistrict litigation proceeding—Most of the Macondo well related claims have been consolidated by the U.S. Judicial Panel on Multidistrict Litigation and transferred to the U.S. District Court for the Eastern District of Louisiana (the “MDL Court”) for pretrial purposes if they were not filed originally in that court. These claims include, inter alia, claims by private parties represented by the Plaintiffs’ Steering Committee (the “PSC”), claims by state and local governments, and the claims of the U.S. As of March 31, 2015, the MDL Court has completed two phases of a trial, and additional litigation is ongoing. Phase One trial—The MDL Court held the Phase One trial between February and April 2013, and entered its Findings of Fact and Conclusions of Law (the “Phase One Ruling”) on September 4, 2014. The trial addressed the claims, cross claims, and counter-claims asserted in our petition to limit liability under the Limitation of Liability Act and the claims asserted by the DOJ in its civil complaint against various defendants. The trial focused on fault issues, including negligence and gross negligence; other bases of liability of the various defendants with respect to the cause of the blowout and the initiation of the oil spill; and fault allocation among the defendants. The Phase One Ruling concluded that BP was grossly negligent and reckless and 67 percent at fault for the blowout, explosion, and spill; that Transocean was negligent and 30 percent at fault; and that Halliburton Company (“Halliburton”) was negligent and three percent at fault. The finding that Transocean was negligent, but not grossly negligent, means that we are not liable for punitive damages. Because the MDL Court found we were not grossly negligent, it concluded that BP’s contractual agreement to indemnify us for compensatory damages caused by pollution that did not originate on or above the surface of the water is valid and enforceable. The MDL Court also ruled that BP’s contractual agreement to release its own claims against us is valid and enforceable. This release bars the PSC from pursuing claims that have purportedly been assigned to it by BP in a settlement reached between BP and the PSC prior to the Phase One trial (see “—Impact of BP/PSC settlement on pending claims”). The MDL Court’s rulings include a number of Transocean-specific findings and conclusions. The MDL Court found that the Deepwater Horizon’s crew was negligent in its conduct of a negative pressure test, which was intended, among other things, to test the integrity of the cement in the well, and in certain well control decisions in the hour before the blowout. The MDL Court found three other bases for imposing negligence liability on Transocean as follows: (1) the crew’s improper diversion of fluids that had entered the riser to the rig’s mud-gas separator instead of overboard; (2) the crew’s failure to properly maintain the blowout preventer; and (3) the master’s failure to timely activate the Emergency Disconnect System as a consequence of an ambiguous command structure. The MDL Court held that these three failures were “within Transocean’s privity and knowledge.” As a result, the MDL Court held that Transocean Holdings LLC, Transocean Deepwater Inc., and Transocean Offshore Deepwater Drilling Inc., three of our wholly owned subsidiaries, could not limit their liability under the Limitation of Liability Act. Under the MDL Court’s ruling, however, we are entitled to indemnity from BP for any compensatory damages caused by pollution that did not originate on or above the surface of the water. The MDL Court also concluded that we were an “operator” of the Macondo well for purposes of 33 U.S.C. § 2704(c)(3), a provision of the Oil Pollution Act (“OPA”) that permits government entities to recover removal costs by owners and operators of a facility or vessel that caused a discharge. The MDL Court, however, reiterated that “Transocean’s liability to government entities for removal costs is ultimately shifted to BP by virtue of contractual indemnity.” The MDL Court released two Transocean entities from liability under general maritime law. First, the MDL Court held that Transocean Ltd. was not liable under general maritime law. The MDL Court also granted a motion for judgment on partial findings by Triton Asset Leasing GmbH, the entity that owned Deepwater Horizon and our wholly owned subsidiary, on the grounds that any negligence or unseaworthiness that caused the blowout arose after the bareboat charter commenced. Following the Phase One Ruling, BP filed a motion to amend the Phase One Findings of Fact and Conclusions of Law, alter or amend the judgment, or for a new trial, alleging the MDL Court made errors in its conclusions about the causes of the failure of the cement in the well. The MDL Court denied the motion. The Phase One Ruling did not quantify damages or result in a final monetary judgment. However, because it is a determination of liability under maritime law, the Phase One Ruling is appealable, and BP, the PSC, Transocean, Halliburton and the State of Alabama have all appealed or cross-appealed aspects of the ruling. The U.S. Court of Appeals for the Fifth Circuit (the “Fifth Circuit”) has issued an order providing that BP and the PSC must file their opening briefs by May 11, 2015. Transocean, Halliburton and the State of Alabama must file their opening briefs within 30 days following the BP and the PSC opening brief filings. Parties must file opposition and reply briefs thereafter. We can provide no assurances as to the outcome of these appeals, as to the timing of any further rulings, or that we will not enter into additional settlements as to some or all of the matters related to the Macondo well incident, including those to be determined at a trial, or the timing or terms of any such settlements. Phase Two trial—The Phase Two of the trial occurred between September 30, 2013 and October 17, 2013. The first segment of the trial addressed BP’s conduct related to stopping the release of hydrocarbons after April 22, 2010, and the second segment addressed quantification of the amount of oil discharged. We participated in the first segment of the trial, but were not a party to the second segment because the ruling as to the quantification of oil primarily relates to setting the statutory maximum civil penalty under the CWA, and we have settled the DOJ’s CWA penalty claim against us. On January 15, 2015, the MDL Court issued its Findings of Facts and Conclusions of Law (the “Phase Two Ruling”). As to the first segment of the trial, the MDL Court ruled that BP was not grossly negligent, reckless, willful or wanton in its source control planning before the spill. The MDL Court declined to decide whether BP was negligent in its planning because it ruled that any negligence finding would not change its fault determinations from Phase One. The MDL Court also found that it had not been shown that BP’s misrepresentation about the flow rate from the well delayed the capping of the well or adversely affected source control, or that post-blowout source control decisions were unreasonable. As to the second segment of the trial, the MDL Court found that four million barrels of oil discharged during the spill. After deducting the barrels that were collected, the MDL Court found that, for purposes of calculating the maximum CWA civil penalty that may be imposed on BP and Anadarko, 3.19 million barrels of oil discharged. Because the Phase One Ruling upheld BP’s indemnity obligation to us, the Phase Two Ruling had no adverse effect on our litigation posture. Several parties have filed notices of appeal from the Phase Two Ruling. Transocean has not appealed the ruling. A briefing schedule has not yet been set for the appeal. Pending claims—As of March 31, 2015, approximately 1,405 actions or claims were pending against us, along with other unaffiliated defendants. These claims were originally filed in various state and federal courts, and most have been consolidated in the MDL Court. Additionally, government agencies have initiated investigations into the Macondo well incident. We have categorized below the nature of these claims. We are vigorously defending all claims and pursuing any and all defenses available. Wrongful death and personal injury claims—As of March 31, 2015, we and certain of our subsidiaries have been named, along with unaffiliated defendants, in nine complaints that were pending in state and federal courts in Louisiana and Texas involving multiple plaintiffs that allege wrongful death and other personal injuries arising out of the Macondo well incident. Nine complaints involve fatalities and 63 complaints seek recovery for bodily injuries. Per the order of the Judicial Panel on Multidistrict Litigation, all claims but one have been centralized for discovery purposes in the MDL Court. The complaints by our employees or representatives of our employees generally allege negligence, unseaworthiness and gross negligence and seek maintenance and cure under the Jones Act and general maritime law and are seeking awards of unspecified economic damages and punitive damages. BP, MI-SWACO, Weatherford International Ltd. and Cameron International Corporation (“Cameron”) and certain of their affiliates, have, based on contractual arrangements, also made indemnity demands upon us with respect to personal injury and wrongful death claims asserted by our employees or representatives of our employees against these entities. See “—Contractual indemnity.” Economic loss and punitive damages claims—As of March 31, 2015, we and certain of our subsidiaries were named, along with other unaffiliated defendants, in 982 pending individual complaints as well as 190 putative class-action complaints that were filed in the federal and state courts in Louisiana, Texas, Mississippi, Alabama, Georgia, Kentucky, South Carolina, Tennessee, Florida and possibly other courts. Most of these complaints have been consolidated in the MDL Court. The complaints generally allege, among other things, economic losses as a result of environmental pollution arising out of the Macondo well incident and are based primarily on OPA, state OPA analogues, and/or general maritime law. The plaintiffs are generally seeking awards of unspecified economic, compensatory and punitive damages, as well as injunctive relief. No classes have been certified at this time. Those plaintiffs who have settled their claims against BP as part of BP’s settlement with the PSC have given up their claims for compensatory damages against us, but purport to retain their claims for punitive damages (see “-Impact of BP/PSC settlement on pending claims”). Cross-claims, counter-claims, and third party claims—Several defendants in the MDL litigation have filed cross-claims or third-party claims against us and certain of our subsidiaries. BP filed a claim seeking contribution under OPA and maritime law and seeking subrogation, and also alleging breach of contract, unseaworthiness, negligence and gross negligence. Through these claims, BP sought to recover from us damages it has paid or may pay arising from the Macondo well incident. BP also sought a declaration that it is not liable in contribution, indemnification, or otherwise to us. BP has assigned some of its claims as part of its settlement with the PSC (see “-Impact of BP/PSC settlement on pending claims”). Certain other parties, including (a) Anadarko Petroleum Corporation (“Anadarko”), which owned a 25 percent non-operating interest in the Macondo well, (b) MOEX Offshore 2007 LLC (“MOEX”), which owned a 10 percent non-operating interest in the Macondo well, (c) Cameron, the manufacturer and designer of the blowout preventer, and (d) Halliburton, which provided cementing and mud-logging services to the operator have asserted claims seeking indemnity and contribution under various theories. BP has reached settlements with certain parties, including Anadarko, MOEX and Cameron, in which BP has agreed to indemnify those parties for certain liabilities, including compensatory damages. We have filed cross-claims and counter-claims against BP, Halliburton, Anadarko, MOEX, certain of these parties’ affiliates, the U.S. and certain other third parties. We seek indemnity, contribution, including contribution under OPA, and subrogation under OPA, and have asserted claims for breach of warranty of workmanlike performance, strict liability for manufacturing and design defect, breach of express contract, and damages for the difference between the fair market value of Deepwater Horizon and the amount received from insurance proceeds. The Consent Decree limits our ability to seek indemnification or reimbursement with respect to payments made under the Consent Decree and dismissed our claims against the U.S. We are not pursuing arbitration on the key contractual issues with BP; instead, we are relying on the court to resolve the disputes. Impact of BP/PSC settlement on pending claims—Before the Phase One trial, in March 2012, BP and the PSC agreed to a partial settlement related primarily to private party environmental and economic loss claims as well as response effort-related claims (the “BP/PSC Settlement”). The BP/PSC Settlement agreement provides that (i) to the extent permitted by law, BP will assign to the settlement class certain of BP’s claims against us for damages, but the settlement class cannot recover from us on those claims unless it is finally determined that we cannot recover such amounts from BP by way of indemnity or any other theory, and (ii) the settlement class releases all claims for compensatory damages against us but purports to retain claims for punitive damages against us. This provision of the settlement became effective on December 8, 2014, when the Supreme Court denied BP’s petition for certiorari seeking review of the trial court’s approval of the settlement. The Phase One Ruling, however, precludes the PSC from recovering on the claims assigned by BP to the settlement class and on the purportedly reserved punitive damages claims (see “-Phase One trial”). On December 21, 2012, the MDL Court granted final approval of the economic and property damage class settlement between BP and the PSC. Various parties who objected to the BP/PSC Settlement appealed the MDL Court’s final approval of the BP/PSC Settlement to the Fifth Circuit, and BP later appealed rulings challenging the manner in which the settlement has been interpreted by the MDL Court. In the appeals by BP, the Fifth Circuit ordered the MDL Court to reconsider certain rulings governing the method by which lost profits are calculated for businesses claiming economic loss, but the Fifth Circuit otherwise affirmed the district court’s interpretation of the settlement agreement. In the appeal by objectors to the settlement, the Fifth Circuit affirmed the MDL Court’s approval of the settlement. The Fifth Circuit subsequently denied BP’s petitions for rehearing in both appeals. On December 8, 2014, the Supreme Court denied BP’s petition for certiorari. Impact of Halliburton/PSC settlement on pending claims—On September 2, 2014, Halliburton and the PSC filed a proposed settlement of the PSC’s punitive damages and assigned claims against Halliburton. The proposed agreement purports to reserve the PSC’s rights to continue pursuing assigned or punitive damages claims against us, but the MDL Court’s Phase One Ruling prevents the PSC from pursuing those claims. The proposed agreement also prohibits the PSC from settling any assigned claims against us unless we agree to release Halliburton from any claims for contribution or indemnity for amounts paid under the settlement. The proposed agreement does not impact Halliburton’s cross-claims and counter claims against us. The MDL Court has not yet approved the settlement. U.S. Department of Justice claims—On December 15, 2010, the DOJ filed a civil lawsuit against us and certain of our subsidiaries and other unaffiliated defendants. The complaint alleged violations under OPA and the CWA. The CWA claims for both monetary and injunctive relief have been resolved through our Consent Decree with the DOJ. See “—Macondo well incident settlement obligations.” The Consent Decree did not resolve the rights of the U.S. with respect to other matters, including certain liabilities under OPA for Natural Resource Damages (“NRD”) or for removal costs. The MDL Court has held that we are not a responsible party under OPA for NRD resulting from discharge of oil from the Macondo well below the surface of the water. If this ruling is upheld on appeal, our NRD liability as a responsible party would be limited to damages arising from any discharge on or above the surface of the water. In the Phase One Ruling, the MDL Court also found that Transocean was the “operator” of the Macondo well and was therefore liable for removal costs under 33 U.S.C. § 2704(c)(3), a separate provision of OPA that permits government entities to recover removal costs from owners and operators of a facility or vessel from which oil discharges. However, the MDL Court found that “Transocean’s liability to government entities for removal costs is ultimately shifted to BP by virtue of the contractual indemnity.” In addition to the civil complaint, the DOJ served us with civil investigative demands on December 8, 2010. These demands were part of an investigation by the DOJ to determine if we made false claims, or false statements in support of claims, in violation of the False Claims Act, in connection with the operator’s acquisition of the leasehold interest in the Mississippi Canyon Block 252, Gulf of Mexico and drilling operations on Deepwater Horizon. The resolution with the DOJ of civil and potential criminal claims did not include potential claims arising from this False Claims Act investigation. As part of the settlement discussions, however, we inquired whether the U.S. intends to pursue any actions under the False Claims Act as discussed below. In response, the DOJ sent us a letter stating that the Civil Division of the DOJ, based on facts then known, was no longer pursuing, and did not have any present intention to pursue any investigation or claims, under the False Claims Act against the various Transocean entities for their involvement in the Macondo well incident. State and other government claims—Claims have been filed against us by over 200 state, local and foreign governments, including the States of Alabama, Florida, Louisiana, Mississippi and Texas; the Mexican States of Veracruz, Quintana Roo, Tamaulipas and Yucatan; the federal government of Mexico and other local governments by and on behalf of multiple towns and parishes. These governments generally assert claims under OPA, other statutory environmental state claims, general maritime law and various other common law claims. A local government master complaint also was filed in the MDL Court in which cities, municipalities, and other local government entities have joined. The MDL Court dismissed damages claims brought under state common and statutory law and subsequently dismissed civil penalty claims brought under state statutory law. Certain Louisiana parishes appealed the dismissal of their civil penalty claims brought under Louisiana law. The Fifth Circuit affirmed the MDL Court’s dismissal of these claims, and the Supreme Court denied certiorari. The state, local and foreign government claims include claims under OPA for economic damages, natural resource damages and removal costs. As noted above, the MDL Court concluded that we were an “operator” of the Macondo well for purposes of OPA. The MDL Court, however, reiterated that “Transocean’s liability to government entities for removal costs is ultimately shifted to BP by virtue of contractual indemnity.” The OPA claims of the Mexican States of Veracruz, Quintana Roo, Tamaulipas and Yucatan were dismissed for failure to demonstrate that recovery under OPA was authorized by treaty or executive agreement. The MDL Court subsequently granted summary judgment on the Mexican States’ general maritime law claims on the ground that the federal government of Mexico, rather than the Mexican States, had the proprietary interest in the property and natural resources allegedly injured by the spill. The Mexican States have appealed the grant of summary judgment on their general maritime law claims to the Fifth Circuit, and the Fifth Circuit heard arguments on October 27, 2014. The claims of the federal government of Mexico remain pending, but under the Phase One Ruling, we are entitled to indemnity from BP for any compensatory damages caused by pollution that did not originate on or above the surface of the water. In addition, by letter dated June 21, 2010, the Attorneys General of the 11 Atlantic Coast states of Connecticut, Delaware, Georgia, Maine, Maryland, Massachusetts, New Hampshire, New York, North Carolina, Rhode Island and South Carolina informed us that their states have not sustained any damage from the Macondo well incident but they would like assurances that we will be responsible financially if damages are sustained. We responded to the letter from the Attorneys General and indicated that we intend to fulfill our obligations as a responsible party for any discharge of oil from Deepwater Horizon on or above the surface of the water, and we assume that the operator and other leaseholders will similarly fulfill their obligations under OPA for discharges from the undersea well. The MDL Court has begun proceeding with respect to Alabama’s compensatory damages claims under OPA and general maritime law. BP has moved to strike Alabama’s demand for a jury trial, and we have joined that motion along with Halliburton. On March 31, 2015, however, the MDL Court denied the motion, ruling that Alabama is entitled to a jury trial on its OPA damages claim. On November 14, 2014, the MDL Court approved a stipulation between us, Alabama, and BP in which the parties agreed that we would be excused from participating in the Alabama compensatory damages trial and in further pretrial proceedings related to that trial. Pursuant to the stipulation, we agreed not to challenge in any future proceeding the amount of compensatory damages, excluding NRD, that may be determined at the trial. The parties further agreed that the amount of damages determined at trial would fully satisfy Alabama’s compensatory damages claims under OPA and general maritime law, excluding NRD, and that certain issues, including what damages, if any, resulted from above-surface discharge, will not be determined in the Alabama compensatory damages trial. Natural Resources Damages Assessment—Under OPA, designated state and federal trustees are authorized to undertake a natural resources damages assessment (“NRDA”) to assess potential natural resource injuries resulting from a discharge of oil or the substantial threat of a discharge and response activities and develop and implement a plan for restoration of injured resources, if any. The trustees invite responsible parties to participate in and fund such efforts. As of March 31, 2015, we have received at least 11 such requests from government agencies. We responded to these requests and declined to participate in the funding on the grounds that we are not a responsible party for discharges from the wellhead. The NRDA trustees are proceeding with the NRDA with funding provided by BP. Citizen suits under environmental statutes—The Center for Biological Diversity (the “Center”), a private environmental group, sued BP, us and certain of our affiliates under multiple federal environmental statutes seeking monetary penalties and injunctive relief. The MDL Court dismissed all of the claims, and in January 2013, the Fifth Circuit affirmed the dismissal with one exception: the Fifth Circuit remanded to the MDL Court the Center’s claim for injunctive relief, but not for penalties, based on BP and Transocean’s alleged failure to make certain reports about the constituents of oil spilled into the U.S. Gulf of Mexico as required by EPCRA. In April 2014, BP and we moved for summary judgment and the Center moved for partial summary judgment against BP. It did not move for partial summary judgment against us, though it purported to reserve its right to do so in the future. The MDL Court has not indicated when it will rule on the motions. Federal securities claims—On September 30, 2010, a proposed federal securities class action was filed in the U.S. District Court for the Southern District of New York, naming us, former chief executive officers of Transocean Ltd. and one of our acquired companies as defendants. In the action, a former shareholder of the acquired company alleged that the joint proxy statement relating to our shareholder meeting in connection with the merger with the acquired company violated Section 14(a) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), Rule 14a-9 promulgated thereunder and Section 20(a) of the Exchange Act. The plaintiff claimed that the acquired company’s shareholders received inadequate consideration for their shares as a result of the alleged violations and sought compensatory and rescissory damages and attorneys’ fees on behalf of the plaintiff and the proposed class members. In connection with this action, we are obligated to pay the defense fees and costs for the individual defendants, which may be covered by our directors’ and officers’ liability insurance, subject to a deductible. On March 11, 2014, the District Court for the Southern District of New York dismissed the claims as time-barred. Plaintiffs appealed to the U.S. Court of Appeals for the Second Circuit and filed an opening brief on December 19, 2014. On February 17, 2015, defendants filed their brief in opposition. On March 3, 2015, plaintiffs filed their reply brief. Oral argument has not yet been scheduled. Wreck removal—By letter dated December 6, 2010, the U.S. Coast Guard requested that we formulate and submit a comprehensive oil removal plan to remove any diesel fuel that can be recovered from Deepwater Horizon. We have conducted a survey of the rig wreckage and have confirmed that no diesel fuel remains on the rig. The U.S. Coast Guard has not requested that we remove the rig wreckage from the sea floor. In February 2013, the U.S. Coast Guard submitted a request seeking analysis and recommendations as to the potential life of the rig’s riser and cofferdam, which are resting on the seafloor and potential remediation or removal options. We have insurance coverage for wreck removal for up to 25 percent of Deepwater Horizon’s insured value, or $140 million, with any excess wreck removal liability generally covered to the extent of our remaining excess liability limits. Insurance coverage—At the time of the Macondo well incident, our excess liability insurance program offered aggregate insurance coverage of $950 million, excluding a $15 million deductible and a $50 million self-insured layer through our wholly owned captive insurance subsidiary. This excess liability insurance coverage consisted of a first and a second layer of $150 million each, a third and fourth layer of $200 million each and a fifth layer of $250 million. The first four excess layers have similar coverage and contractual terms, while the $250 million fifth layer is on a different policy form, which varies to some extent from the underlying coverage and contractual terms. Generally, we believe that the policy forms for all layers include coverage for personal injury and fatality claims, subject to reasonableness determinations, of our crew and vendors, for which indemnity agreements are in place as to the latter, actual and compensatory damages, punitive damages and related legal defense costs. The policy forms for the first four excess layers provide coverage for fines; however, we do not expect payments deemed to be criminal in nature to be covered by any of the layers. In May 2010, we received notice from BP claiming an entitlement to unlimited additional insured status under our excess liability insurance program. Our insurers have also received notices from Anadarko and MOEX advising of their intent to preserve any rights they may have to our insurance policies as an additional insured under the drilling contract. In response, our wholly owned captive insurance subsidiary and our first four excess layer insurers filed declaratory judgment actions in the Houston Division of the U.S. District Court for the Southern District of Texas in May 2010 seeking a declaration that they have limited additional insured obligations to BP. We are parties to the declaratory judgment actions, which were transferred to the MDL Court for discovery and other purposes. On November 15, 2011, the MDL Court ruled that BP’s coverage rights are limited to the scope of our indemnification of BP in the drilling contract. A final judgment was entered against BP, Anadarko and MOEX, and BP appealed. On March 1, 2013, the Fifth Circuit issued an opinion reversing the decision of the MDL Court, and holding that BP is an unrestricted additional insured under the policies issued by our wholly owned captive insurance company and the first four excess layer insurers. We and the insurers filed petitions for rehearing with the Fifth Circuit. On August 29, 2013, the Fifth Circuit withdrew the March 1, 2013 opinion and certified certain insurance law questions to the Texas Supreme Court. The Texas Supreme Court accepted certification of these questions, and the oral argument was held on September 16, 2014. On February 13, 2015, the Texas Supreme Court issued its answer to one of the Fifth Circuit’s questions by determining that BP is not entitled to coverage under certain of our insurance policies for damages arising from subsurface pollution because BP assumed, and we did not assume, liability for such claims. BP is seeking rehearing by the Texas Supreme Court. We believe that additional insured coverage for BP, Anadarko or MOEX under the $250 million fifth layer of our insurance program is limited to the scope of our indemnification of BP under the drilling contract. While we cannot predict the outcome of any subsequent proceedings in the Texas Supreme Court or the Fifth Circuit, we do not expect them to have a material adverse effect on our consolidated statement of financial position, results of operations or cash flows. On June 17, 2011 and July 31, 2012, our first layer and second layer of excess insurers, respectively, each representing $150 million of insurance coverage, filed interpleader actions. On February 14, 2013, the third and fourth layers, each representing $200 million of insurance coverage, filed interpleader actions substantially similar to those of the first and second layers. The insurers contend that they face multiple, and potentially competing, claims to the relevant insurance proceeds. In these actions, the insurers effectively ask the court to manage disbursement of the funds to the alleged claimants, as appropriate, and discharge the insurers of any additional liability. The parties to the first and second excess insurer interpleader actions have executed protocol agreements to facilitate the reimbursement and funding of settlements of personal injury and fatality claims of our crew and vendors (collectively, “crew claims”) using insurance funds and claims were submitted to the court for review. Following the court’s determination and approval of the amounts to be paid by the insurers with respect to the crew claims submitted by the parties, the first layer of excess insurers made reimbursement payments to the parties for crew claims during the years ended December 31, 2013 and 2014. Additional claims may be submitted to the court for a determination and approval of the amounts insurers owe. Parties to the third and fourth excess insurer interpleader actions have agreed to adjourn the deadline for responses to the pleadings to an unspecified date that will follow a decision in another action that pertains to our insurance. Contractual indemnity—Under our drilling contract for Deepwater Horizon, BP has agreed, among other things, to assume responsibility for and defend, release and indemnify us from any loss, expense, claim, fine, penalty or liability for pollution or contamination, including control and removal thereof, arising out of or connected with operations under the contract other than those for pollution or contamination originating on or above the surface of the water from hydrocarbons or other specified substances within our control and possession, as to which we agreed to assume responsibility and protect, release and indemnify BP. Although we do not believe it is applicable to the Macondo well incident, we also agreed to indemnify and defend BP up to a limit of $15 million for claims for loss or damage to third parties arising from pollution caused by the rig while it is off the drilling location, while the rig is underway or during drive off or drift off of the rig from the drilling location. BP has also agreed, among other things, (i) to defend, release and indemnify us against loss or damage to the reservoir, and loss of property rights to oil, gas and minerals below the surface of the earth and (ii) to defend, release and indemnify us and bear the cost of bringing the well under control in the event of a blowout or other loss of control. We agreed to defend, release and indemnify BP for personal injury and death of our employees and the employees of our contractors while BP agreed to defend, release and indemnify us for personal injury and death of its employees and the employees of its contractors, other than us. We also agreed to defend, release and indemnify BP for damages to the rig and equipment, including salvage or removal costs. BP has sought to avoid its indemnification obligations. On January 26, 2012, the MDL Court ruled that the drilling contract requires BP to indemnify us for compensatory damages sought by third parties related to pollution that did not originate from the rig on or above the surface of the water, regardless of whether the claim is the result of our strict liability, negligence, or gross negligence. The MDL Court ruled that BP had a contractual duty to defend us, but that the duty to defend only required BP to reimburse our defense costs after there is a judicial determination on the merits. The MDL Court did not rule on the scope of BP’s duty to defend, although it did rule that BP is not obligated to pay the attorneys’ fees incurred by us in proving our right to indemnification. The MDL Court also held that BP does not owe us indemnity for civil penalties under the CWA or punitive damages. We subsequently agreed, as part of our Consent Decree not to seek indemnity or reimbursement of our CWA civil penalty payments from BP or the other non-insurer defendants named in the complaint by the U.S. The MDL Court’s 2012 order deferred ruling on BP’s argument that we committed a core breach of the drilling contract or otherwise materially increased BP’s risk or prejudiced its rights so as to vitiate BP’s indemnity obligations. In the Phase One Ruling, however, the MDL Court found we were not grossly negligent and otherwise upheld the indemnities, implicitly finding no core breach of contract occurred. The impact of this ruling is that BP is obligated to indemnify us as provided for in the contract and that we are entitled to recover certain of our attorneys’ fees from BP as a result of its contractual duty to defend us. The MDL Court has not ruled on the issue of whether contractual indemnity for criminal fines and penalties is enforceable, but the law generally considers contractual indemnity for criminal fines and penalties to be against public policy. In the Phase One Ruling, the MDL Court noted that a finding of gross negligence against us would have invalidated BP’s release, in the drilling contract of its direct claims against us. As a result of the MDL Court’s finding of simple negligence as to us, however, the MDL Court ruled that BP’s release of its claims against us is valid and enforceable. Accordingly, the PSC is precluded from pursuing BP’s direct claims against us that were assigned to the PSC as part of the BP/PSC Settlement. This ruling and the MDL Court’s other rulings regarding indemnity may be challenged in the pending appeals from the Phase One Ruling. Other legal proceedings Asbestos litigation—In 2004, several of our subsidiaries were named, along with numerous other unaffiliated defendants, in 21 complaints filed on behalf of 769 plaintiffs in the Circuit Courts of the State of Mississippi and which claimed injuries arising out of exposure to asbestos allegedly contained in drilling mud during these plaintiffs’ employment in drilling activities between 1965 and 1986. The complaints generally allege that the defendants used or manufactured asbestos containing drilling mud additives for use in connection with drilling operations and have included allegations of negligence, products liability, strict liability and claims allowed under the Jones Act and general maritime law. In each of these cases, the complaints have named other unaffiliated defendant companies, including companies that allegedly manufactured the drilling-related products that contained asbestos. The plaintiffs generally seek awards of unspecified compensatory and punitive damages, but the court-appointed special master has ruled that a Jones Act employer defendant, such as us, cannot be sued for punitive damages. After ten years of litigation, this group of cases has been winnowed to the point where now only 15 plaintiffs’ individual claims remain pending in Mississippi in which we have or may have an interest. During the year ended December 31, 2014, a group of lawsuits premised on the same allegations as those in Mississippi were filed in Louisiana. As of March 31, 2015, eight plaintiffs have claims pending against one or more of our subsidiaries in four different lawsuits filed in Louisiana. We intend to defend these lawsuits vigorously, although we can provide no assurance as to the outcome. We historically have maintained broad liability insurance, although we are not certain whether insurance will cover the liabilities, if any, arising out of these claims. Based on our evaluation of the exposure to date, we do not expect the liability, if any, resulting from these claims to have a material adverse effect on our consolidated statement of financial position, results of operations or cash flows. One of our subsidiaries was involved in lawsuits arising out of the subsidiary’s involvement in the design, construction and refurbishment of major industrial complexes. The operating assets of the subsidiary were sold and its operations discontinued in 1989, and the subsidiary has no remaining assets other than the insurance policies involved in its litigation, with its insurers and, either directly or indirectly through a qualified settlement fund. The subsidiary has been named as a defendant, along with numerous other companies, in lawsuits alleging bodily injury or personal injury as a result of exposure to asbestos. As of March 31, 2015, the subsidiary was a defendant in approximately 693 lawsuits, some of which include multiple plaintiffs, and we estimate that there are approximately 945 plaintiffs in these lawsuits. For many of these lawsuits, we have not been provided with sufficient information from the plaintiffs to determine whether all or some of the plaintiffs have claims against the subsidiary, the basis of any such claims, or the nature of their alleged injuries. The first of the asbestos-related lawsuits was filed against the subsidiary in 1990. Through March 31, 2015, the costs incurred to resolve claims, including both defense fees and expenses and settlement costs, have not been material, all known deductibles have been satisfied or are inapplicable, and the subsidiary’s defense fees and expenses and settlement costs have been met by insurance made available to the subsidiary. The subsidiary continues to be named as a defendant in additional lawsuits, and we cannot predict the number of additional cases in which it may be named a defendant nor can we predict the potential costs to resolve such additional cases or to resolve the pending cases. However, the subsidiary has in excess of $1.0 billion in insurance limits potentially available to the subsidiary. Although not all of the policies may be fully available due to the insolvency of certain insurers, we believe that the subsidiary will have sufficient funding directly or indirectly from settlements and claims payments from insurers, assigned rights from insurers and coverage-in-place settlement agreements with insurers to respond to these claims. While we cannot predict or provide assurance as to the outcome of these matters, we do not believe that the ultimate liability, if any, arising from these claims will have a material impact on our consolidated statement of financial position, results of operations or cash flows. Rio de Janeiro tax assessment—In the third quarter of 2006, we received tax assessments of BRL 428 million, equivalent to approximately $134 million, including interest and penalties, from the state tax authorities of Rio de Janeiro in Brazil against one of our Brazilian subsidiaries for taxes on equipment imported into the state in connection with our operations. The assessments resulted from a preliminary finding by these authorities that our record keeping practices were deficient. We currently believe that the substantial majority of these assessments are without merit. We filed an initial response with the Rio de Janeiro tax authorities on September 9, 2006 refuting these additional tax assessments. In September 2007, we received confirmation from the state tax authorities that they believe the additional tax assessments are valid, and as a result, we filed an appeal on September 27, 2007 to the state Taxpayer’s Council contesting these assessments. While we cannot predict or provide assurance as to the final outcome of these proceedings, we do not expect it to have a material adverse effect on our consolidated statement of financial position, results of operations or cash flows. Brazilian import license assessment—In the fourth quarter of 2010, we received an assessment from the Brazilian federal tax authorities in Rio de Janeiro of BRL 539 million, equivalent to approximately $169 million, including interest and penalties, based upon the alleged failure to timely apply for import licenses for certain equipment and for allegedly providing improper information on import license applications. We believe that a substantial majority of the assessment is without merit and are vigorously pursuing legal remedies. The case was decided partially in favor of our Brazilian subsidiary in the lower administrative court level. The decision cancelled the majority of the assessment, reducing the total assessment to BRL 36 million, equivalent to approximately $11 million. On July 14, 2011, we filed an appeal to eliminate the assessment. On May 23, 2013, a ruling was issued that eliminated all assessment amounts. A further appeal by the taxing authorities was filed in November 2014. While we cannot predict or provide assurance as to the outcome of these proceedings, we do not expect it to have a material adverse effect on our consolidated statement of financial position, results of operations or cash flows. Petrobras withholding taxes—In July 2014, we received letters from Petróleo Brasileiro S.A. (“Petrobras”) informing us that the Brazilian Federal Revenue Service (the “RFB”) is assessing Petrobras for withholding taxes presumably due and unpaid on payments made in 2008 and 2009 to beneficiaries domiciled outside of Brazil in connection with the charter agreements related to work performed by its contractors, including us. Petrobras contracts include a structure for chartering vessels owned by entities not domiciled in Brazil. Petrobras is challenging such tax assessment and has indicated that, if it loses the tax dispute, it will seek to recover from its contractors, including us, any taxes, penalties, interest and fees that Petrobras is being requested to pay. Petrobras has informed us that it has received from the RFB notices of deficiencies for BRL 283 million, equivalent to approximately $89 million, excluding penalties, interest and fees, related to work performed by us. We have informed Petrobras that we believe it has no basis for seeking reimbursement from us, and we intend to vigorously challenge any assertions to the contrary. Effective January 1, 2015, the Brazilian Government enacted a new law that expressly applies zero rate withholding to charter payments made in connection with a vessel to a beneficiary domiciled outside of Brazil when the agreement is entered into jointly with a services contract to operate the vessel. All of our charter contracts with Petrobras met the criteria for such withholding. While the law and ruling are not retroactive, such rulings strengthen Petrobras’ argument for challenging the tax assessment. An unfavorable outcome on these matters could result in a material adverse effect on our consolidated statement of financial position, results of operations or cash flows. Nigerian Cabotage Act litigation—In October 2007, three of our subsidiaries were each served a Notice and Demand from the Nigeria Maritime Administration and Safety Agency, imposing a two percent surcharge on the value of all contracts performed by us in Nigeria pursuant to the Coastal and Inland Shipping (Cabotage) Act 2003 (the “Cabotage Act”). Our subsidiaries each filed an originating summons in the Federal High Court in Lagos challenging the imposition of this surcharge on the basis that the Cabotage Act and associated levy is not applicable to drilling rigs. The respondents challenged the competence of the suits on several procedural grounds. The court upheld the objections and dismissed the suits. In December 2010, our subsidiaries filed a new joint Cabotage Act suit. While we cannot predict or provide assurance as to the outcome of these proceedings, we do not expect it to have a material adverse effect on our consolidated statement of financial position, results of operations or cash flows. Other matters—We are involved in various tax matters, various regulatory matters, and a number of claims and lawsuits, asserted and unasserted, all of which have arisen in the ordinary course of our business. We do not expect the liability, if any, resulting from these other matters to have a material adverse effect on our consolidated statement of financial position, results of operations or cash flows. We cannot predict with certainty the outcome or effect of any of the litigation matters specifically described above or of any such other pending, threatened, or possible litigation or liability. We can provide no assurance that our beliefs or expectations as to the outcome or effect of any tax, regulatory, lawsuit or other litigation matter will prove correct and the eventual outcome of these matters could materially differ from management’s current estimates. Other environmental matters Hazardous waste disposal sites—We have certain potential liabilities under CERCLA and similar state acts regulating cleanup of various hazardous waste disposal sites, including those described below. CERCLA is intended to expedite the remediation of hazardous substances without regard to fault. Potentially responsible parties (“PRPs”) for each site include present and former owners and operators of, transporters to and generators of the substances at the site. Liability is strict and can be joint and several. We have been named as a PRP in connection with a site located in Santa Fe Springs, California, known as the Waste Disposal, Inc. site. We and other PRPs have agreed with the EPA and the DOJ to settle our potential liabilities for this site by agreeing to perform the remaining remediation required by the EPA. The form of the agreement is a consent decree, which has been entered by the court. The parties to the settlement have entered into a participation agreement, which makes us liable for approximately eight percent of the remediation and related costs. The remediation is complete, and we believe our share of the future operation and maintenance costs of the site is not material. There are additional potential liabilities related to the site, but these cannot be quantified, and we have no reason at this time to believe that they will be material. One of our subsidiaries has been ordered by the California Regional Water Quality Control Board (“CRWQCB”) to develop a testing plan for a site known as Campus 1000 Fremont in Alhambra, California. This site was formerly owned and operated by certain of our subsidiaries. It is presently owned by an unrelated party, which has received an order to test the property. We have also been advised that one or more of our subsidiaries is likely to be named by the EPA as a PRP for the San Gabriel Valley, Area 3, Superfund site, which includes this property. Testing has been completed at the property, but no contaminants of concern were detected. In discussions with CRWQCB staff, we were advised of their intent to issue us a “no further action” letter, but it has not yet been received. Based on the test results, we would contest any potential liability. We have no knowledge at this time of the potential cost of any remediation, who else will be named as PRPs, and whether in fact any of our subsidiaries is a responsible party. The subsidiaries in question do not own any operating assets and have limited ability to respond to any liabilities. Resolutions of other claims by the EPA, the involved state agency or PRPs are at various stages of investigation. These investigations involve determinations of (a) the actual responsibility attributed to us and the other PRPs at the site, (b) appropriate investigatory or remedial actions and (c) allocation of the costs of such activities among the PRPs and other site users. Our ultimate financial responsibility in connection with those sites may depend on many factors, including (i) the volume and nature of material, if any, contributed to the site for which we are responsible, (ii) the number of other PRPs and their financial viability and (iii) the remediation methods and technology to be used. It is difficult to quantify with certainty the potential cost of these environmental matters, particularly in respect of remediation obligations. Nevertheless, based upon the information currently available, we believe that our ultimate liability arising from all environmental matters, including the liability for all other related pending legal proceedings, asserted legal claims and known potential legal claims which are likely to be asserted, is adequately accrued and should not have a material effect on our consolidated statement of financial position or results of operations. Retained risk Overview—Our hull and machinery and excess liability insurance program is comprised of commercial market and captive insurance policies that we renew annually on May 1. We periodically evaluate our insurance limits and self-insured retentions. At March 31, 2015, the insured value of our drilling rig fleet was approximately $27.6 billion, excluding our rigs under construction. We generally do not carry commercial market insurance coverage for loss of revenues or for losses resulting from physical damage to our fleet caused by named windstorms in the U.S. Gulf of Mexico, including liability for wreck removal costs. Hull and machinery coverage—At March 31, 2015, under the hull and machinery program, we generally maintained a $125 million per occurrence deductible, limited to a maximum of $200 million per policy period. Subject to the same shared deductible, we also had coverage for an amount equal to 50 percent of a rig’s insured value for combined costs incurred to mitigate rig damage, wreck or debris removal and collision liability. Any excess wreck or debris removal costs and excess collision liability costs are generally covered to the extent of our remaining excess liability coverage. Excess liability coverage—At March 31, 2015, we carried excess liability coverage of $700 million in the commercial market excluding the deductibles and self-insured retention noted below, which generally covers offshore risks such as personal injury, third-party property claims, and third-party non-crew claims, including wreck removal and pollution. Our excess liability coverage had separate $10 million per occurrence deductibles on collision liability claims and $5 million per occurrence deductibles on crew personal injury claims and on other third-party non-crew claims. Through our wholly owned captive insurance company, we retained the risk of the primary $50 million excess liability coverage. In addition, we generally retained the risk for any liability losses in excess of $750 million. Other insurance coverage—At March 31, 2015, we also carried $100 million of additional insurance that generally covers expenses that would otherwise be assumed by the well owner, such as costs to control the well, redrill expenses and pollution from the well. This additional insurance provides coverage for such expenses in circumstances in which we have legal or contractual liability arising from our gross negligence or willful misconduct. Letters of credit and surety bonds At March 31, 2015 and December 31, 2014, we had outstanding letters of credit totaling $305 million and $338 million, respectively, issued under various committed and uncommitted credit lines provided by several banks to guarantee various contract bidding, performance activities and customs obligations, including letters of credit totaling $79 million and $91 million, respectively, that we agreed to maintain in support of the operations for Shelf Drilling (see Note 7—Discontinued Operations). As is customary in the contract drilling business, we also have various surety bonds in place that secure customs obligations relating to the importation of our rigs and certain performance and other obligations. At March 31, 2015 and December 31, 2014, we had outstanding surety bonds totaling $6 million.

- Definition

The entire disclosure for commitments and contingencies.

+ References+ Details

Shareholders' Equity

3 Months Ended

Mar. 31, 2015

Shareholders' Equity

Shareholders' Equity

Note 14—Shareholders’ Equity

Distributions of qualifying additional paid-in capital—On February 15, 2015, our board of directors announced its recommendation that our shareholders at the 2015 annual general meeting approve a distribution of qualifying additional paid-in capital in the form of a U.S. dollar denominated dividend of $0.60 per outstanding share, payable in four quarterly installments of $0.15 per outstanding share, subject to certain limitations. If approved, we expect that the dividend installments will be paid in June 2015, September 2015, December 2015 and March 2016.

In May 2014, at our annual general meeting, our shareholders approved the distribution of qualifying additional paid-in capital in the form of a U.S. dollar denominated dividend of $3.00 per outstanding share, payable in four quarterly installments of $0.75 per outstanding share, subject to certain limitations. At December 31, 2014, the aggregate carrying amount of the distribution payable was $272 million. On March 18, 2015, we paid the final installment in the aggregate amount of $272 million to shareholders of record as of February 20, 2015.

In May 2013, at our annual general meeting, our shareholders approved the distribution of qualifying additional paid-in capital in the form of a U.S. dollar denominated dividend of $2.24 per outstanding share, payable in four quarterly installments of $0.56 per outstanding share, subject to certain limitations. On March 19, 2014, we paid the final installment in the aggregate amount of $202 million to shareholders of record as of February 21, 2014.

Shares held by subsidiary—One of our subsidiaries holds our shares for future use to satisfy our obligations to deliver shares in connection with awards granted under our incentive plans or other rights to acquire our shares. At March 31, 2015 and December 31, 2014, our subsidiary held 7.6 million shares and 8.7 million shares, respectively.

Accumulated other comprehensive loss—The changes in accumulated other comprehensive loss, presented net of tax, were as follows (in millions):

	Three months ended March 31, 2015								Three months ended March 31, 2014
	Defined benefit pension plans			Derivative instruments		Total			Defined benefit pension plans			Derivative instruments			Total
Balance, beginning of period	$	(404	)	$	—	$	(404	)	$	(264	)	$	2		$	(262	)
Other comprehensive loss before reclassifications	(11		)	—		(11		)	(5		)	—			(5		)
Reclassifications to net income	1			—		1			6			(2		)	4
Other comprehensive income (loss), net	(10		)	—		(10		)	1			(2		)	(1		)
Balance, end of period	$	(414	)	$	—	$	(414	)	$	(263	)	$	—		$	(263	)

Significant reclassifications from accumulated other comprehensive income to net income included the following (in millions):

		Three months ended March 31,
	Statement of operations classification	2015			2014
Defined benefit pension plans
Actuarial losses		$	5		$	6
Total amortization, before income taxes	Net periodic benefit costs (a)	5			6
Income tax benefit	Income tax expense	(4		)	—
Total amortization, net of income taxes		$	1		$	6

(a)

We recognize the amortization of accumulated other comprehensive income components related to defined benefit pension plans in net periodic benefit costs. In the three months ended March 31, 2015, our net periodic benefit costs included $4 million and $1 million, recorded in operating and maintenance costs and general and administrative costs, respectively. In the three months ended March 31, 2014, our net periodic benefit costs included $4 million and $2 million, recorded in operating and maintenance costs and general and administrative costs, respectively. See Note 12—Postemployment Benefit Plans.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29-31)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30, 31

-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 4.E)

-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74512-122707

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 4

-Subparagraph (SAB TOPIC 4.C)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Article 4

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 4

-Section C

Reference 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 4

-Section E

Reference 9: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(d),(e))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 10: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Preferred Stock

-URI http://asc.fasb.org/extlink&oid=6521494

Reference 11: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 12: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 13: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 14: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 15: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21564-112644

Reference 16: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21488-112644

Reference 17: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21484-112644

Reference 18: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph d

-Article 4

Reference 19: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6405834&loc=d3e23285-112656

+ Details

Noncontrolling Interest	3 Months Ended
Noncontrolling Interest	Mar. 31, 2015
Noncontrolling interest
Noncontrolling interest	Note 15—Noncontrolling interest In the three months ended March 31, 2015, Transocean Partners declared and paid an aggregate distribution of $25 million to its unitholders of record as of February 20, 2015, of which $18 million was paid to us and was eliminated in consolidation.

- Definition

The entire disclosure for noncontrolling interest in consolidated subsidiaries, which could include the name of the subsidiary, the ownership percentage held by the parent, the ownership percentage held by the noncontrolling owners, the amount of the noncontrolling interest, the location of this amount on the balance sheet (when not reported separately), an explanation of the increase or decrease in the amount of the noncontrolling interest, the noncontrolling interest share of the net Income or Loss of the subsidiary, the location of this amount on the income statement (when not reported separately), the nature of the noncontrolling interest such as background information and terms, the amount of the noncontrolling interest represented by preferred stock, a description of the preferred stock, and the dividend requirements of the preferred stock.

+ References+ Details

Financial Instruments

3 Months Ended

Mar. 31, 2015

Financial Instruments

Financial Instruments

Note 16—Financial Instruments

The carrying amounts and fair values of our financial instruments were as follows (in millions):

	March 31, 2015				December 31, 2014
	Carrying amount		Fair value		Carrying amount		Fair value
Cash and cash equivalents	$	2,682	$	2,682	$	2,635	$	2,635
Notes and other loans receivable	15		15		15		15
Restricted cash investments	296		309		377		394
Long-term debt, including current maturities	10,020		8,834		10,092		9,778
Derivative instruments, assets	33		33		15		15

We estimated the fair value of each class of financial instruments, for which estimating fair value is practicable, by applying the following methods and assumptions:

Cash and cash equivalents—The carrying amount of cash and cash equivalents represents the historical cost, plus accrued interest, which approximates fair value because of the short maturities of those instruments. We measured the estimated fair value of our cash equivalents using significant other observable inputs, representative of a Level 2 fair value measurement, including the net asset values of the investments. At March 31, 2015 and December 31, 2014, the aggregate carrying amount of our cash equivalents was $1.8 billion and $1.7 billion, respectively.

Notes and other loans receivable—We hold certain notes and other loans receivable, which originated in connection with certain asset dispositions and supplier advances. The carrying amount represents the amortized cost of our investments. We measured the estimated fair value using significant unobservable inputs, representative of a Level 3 fair value measurement, including the credit ratings of the borrowers. At March 31, 2015 and December 31, 2014, the aggregate carrying amount of our notes receivable and other loans receivable was $15 million, recorded in other assets.

Restricted cash investments—The carrying amount of the Eksportfinans Restricted Cash Investments represents the amortized cost of our investment. We measured the estimated fair value of the Eksportfinans Restricted Cash Investments using significant other observable inputs, representative of a Level 2 fair value measurement, including the terms and credit spreads of the instruments. At March 31, 2015 and December 31, 2014, the aggregate carrying amount of the Eksportfinans Restricted Cash Investments was $288 million and $369 million, respectively. At March 31, 2015 and December 31, 2014, the estimated fair value of the Eksportfinans Restricted Cash Investments was $301 million and $386 million, respectively.

The carrying amount of the restricted cash investments for certain contingent obligations approximates fair value due to the short term nature of the instruments in which the restricted cash investments are held. At March 31, 2015 and December 31, 2014, the aggregate carrying amount of the restricted cash investments for certain contingent obligations was $8 million, recorded in other current liabilities.

Debt—We measured the estimated fair value of our fixed-rate debt using significant other observable inputs, representative of a Level 2 fair value measurement, including the terms and credit spreads for the instruments. At March 31, 2015 and December 31, 2014, the aggregate carrying amount of our fixed-rate debt was $10.0 billion and $10.1 billion, respectively. At March 31, 2015 and December 31, 2014, the aggregate estimated fair value of our fixed-rate debt was $8.8 billion and $9.8 billion, respectively.

Derivative instruments—The carrying amount of our derivative instruments represents the estimated fair value. We measured the estimated fair value using significant other observable inputs, representative of a Level 2 fair value measurement, including the interest rates and terms of the instruments.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References+ Details

Condensed Consolidating Financial Information

3 Months Ended

Mar. 31, 2015

Condensed Consolidating Financial Information

Condensed Consolidating Financial Information

Note 17—Condensed Consolidating Financial Information

Transocean Inc., a wholly owned subsidiary of Transocean Ltd., is the issuer of certain notes and debentures, which have been guaranteed by Transocean Ltd. Transocean Ltd.’s guarantee of debt securities of Transocean Inc. is full and unconditional. Transocean Ltd. is not subject to any significant restrictions on its ability to obtain funds by dividends, loans or return of capital distributions from its consolidated subsidiaries.

The following tables present condensed consolidating financial information for (a) Transocean Ltd. (the “Parent Guarantor”), (b) Transocean Inc. (the “Subsidiary Issuer”), and (c) the other direct and indirect wholly owned and partially owned subsidiaries of the Parent Guarantor, none of which guarantee any indebtedness of the Subsidiary Issuer (the “Other Subsidiaries”). The condensed consolidating financial information may not necessarily be indicative of the results of operations, financial position or cash flows had the subsidiaries operated as independent entities.

The following tables include the consolidating adjustments necessary to present the condensed financial statements on a consolidated basis (in millions):

	Three months ended March 31, 2015
	Parent Guarantor			Subsidiary Issuer			Other Subsidiaries			Consolidating adjustments		Consolidated
Operating revenues	$	—		$	—		$	2,043		$	—	$	2,043
Cost and expenses	4			2			1,415			—		1,421
Loss on impairment	—			—			(936		)	—		(936		)
Loss on disposal of assets, net	—			—			(7		)	—		(7		)
Operating loss	(4		)	(2		)	(315		)	—		(321		)

Other income (expense), net
Interest income (expense), net	—			(161		)	51			—		(110		)
Equity in earnings	(479		)	(268		)	—			747		—
Other, net	—			39			8			—		47
	(479		)	(390		)	59			747		(63		)
Loss from continuing operations before income tax expense	(483		)	(392		)	(256		)	747		(384		)
Income tax expense	—			—			83			—		83
Loss from continuing operations	(483		)	(392		)	(339		)	747		(467		)
Gain (loss) from discontinued operations, net of tax	—			1			(3		)	—		(2		)

Net loss	(483		)	(391		)	(342		)	747		(469		)
Net income attributable to noncontrolling interest	—			—			14			—		14
Net loss attributable to controlling interest	(483		)	(391		)	(356		)	747		(483		)

Other comprehensive income (loss) before income taxes	(2		)	(9		)	3			—		(8		)
Income taxes related to other comprehensive loss	—			—			(2		)	—		(2		)
Other comprehensive income (loss), net of income taxes	(2		)	(9		)	1			—		(10		)

Total comprehensive loss	(485		)	(400		)	(341		)	747		(479		)
Total comprehensive income attributable to noncontrolling interest	—			—			14			—		14
Total comprehensive loss attributable to controlling interest	$	(485	)	$	(400	)	$	(355	)	$	747	$	(493	)

	Three months ended March 31, 2014
	Parent Guarantor			Subsidiary Issuer			Other Subsidiaries			Consolidating adjustments			Consolidated
Operating revenues	$	—		$	—		$	2,343		$	(4	)	$	2,339
Cost and expenses	9			1			1,593			(4		)	1,599
Loss on impairment	—			—			(65		)	—			(65		)
Loss on disposal of assets, net	—			—			(3		)	—			(3		)
Operating income (loss)	(9		)	(1		)	682			—			672

Other income (expense), net
Interest income (expense), net	6			139			(261		)	—			(116		)
Equity in earnings	459			287			—			(746		)	—
Other, net	—			1			(3		)	—			(2		)
	465			427			(264		)	(746		)	(118		)
Income from continuing operations before income tax expense	456			426			418			(746		)	554
Income tax expense	—			—			80			—			80
Income from continuing operations	456			426			338			(746		)	474
Gain (loss) from discontinued operations, net of tax	—			4			(12		)	—			(8		)

Net Income	456			430			326			(746		)	466
Net income attributable to noncontrolling interest	—			—			10			—			10
Net income attributable to controlling interest	456			430			316			(746		)	456

Other comprehensive income (loss) before income taxes	(2		)	(6		)	7			—			(1		)
Income taxes related to other comprehensive loss	—			—			—			—			—
Other comprehensive income (loss), net of income taxes	(2		)	(6		)	7			—			(1		)

Total comprehensive income	454			424			333			(746		)	465
Total comprehensive income attributable to noncontrolling interest	—			—			10			—			10
Total comprehensive income attributable to controlling interest	$	454		$	424		$	323		$	(746	)	$	455

	March 31, 2015
	Parent Guarantor		Subsidiary Issuer		Other Subsidiaries		Consolidating adjustments			Consolidated
Assets
Cash and cash equivalents	$	19	$	1,160	$	1,503	$	—		$	2,682
Other current assets	3		741		4,908		(2,491		)	3,161
Total current assets	22		1,901		6,411		(2,491		)	5,843

Property and equipment, net	—		—		20,566		—			20,566
Investment in affiliates	13,210		30,270		—		(43,480		)	—
Other assets	—		4,241		26,637		(30,182		)	696
Total assets	13,232		36,412		53,614		(76,153		)	27,105

Liabilities and equity
Debt due within one year	—		896		128		—			1,024
Other current liabilities	6		465		4,169		(2,491		)	2,149
Total current liabilities	6		1,361		4,297		(2,491		)	3,173

Long-term debt	—		22,217		16,961		(30,182		)	8,996
Other long-term liabilities	25		285		1,105		—			1,415
Total long-term liabilities	25		22,502		18,066		(30,182		)	10,411

Commitments and contingencies
Redeemable noncontrolling interest	—		—		11		—			11

Total equity	13,201		12,549		31,240		(43,480		)	13,510
Total liabilities and equity	$	13,232	$	36,412	$	53,614	$	(76,153	)	$	27,105

	December 31, 2014
	Parent Guarantor		Subsidiary Issuer		Other Subsidiaries		Consolidating adjustments			Consolidated
Assets
Cash and cash equivalents	$	16	$	842	$	1,777	$	—		$	2,635
Other current assets	12		757		5,228		(2,631		)	3,366
Total current assets	28		1,599		7,005		(2,631		)	6,001

Property and equipment, net	—		—		21,538		—			21,538
Investment in affiliates	13,952		30,925		—		(44,877		)	—
Other assets	—		3,899		25,883		(28,908		)	874
Total assets	13,980		36,423		54,426		(76,416		)	28,413

Liabilities and equity
Debt due within one year	—		898		135		—			1,033
Other current liabilities	287		473		4,608		(2,631		)	2,737
Total current liabilities	287		1,371		4,743		(2,631		)	3,770

Long-term debt	—		21,486		16,481		(28,908		)	9,059
Other long-term liabilities	22		280		1,289		—			1,591
Total long-term liabilities	22		21,766		17,770		(28,908		)	10,650

Commitments and contingencies
Redeemable noncontrolling interest	—		—		11		—			11

Total equity	13,671		13,286		31,902		(44,877		)	13,982
Total liabilities and equity	$	13,980	$	36,423	$	54,426	$	(76,416	)	$	28,413

	Three months ended March 31, 2015
	Parent Guarantor			Subsidiary Issuer			Other Subsidiaries			Consolidating adjustments			Consolidated

Cash flows from operating activities	$	2		$	(75	)	$	599		$	—		$	526

Cash flows from investing activities
Capital expenditures	—			—			(201		)	—			(201		)
Proceeds from disposal of assets, net	—			—			7			—			7
Proceeds from disposal of assets in discontinued operations, net	—			—			2			—			2
Investing activities with affiliates, net	—			(353		)	(746		)	1,099			—
Net cash used in investing activities	—			(353		)	(938		)	1,099			(192		)

Cash flows from financing activities
Repayments of debt	—			—			(63		)	—			(63		)
Proceeds from restricted cash investments	—			—			57			—			57
Distribution of qualifying additional paid-in capital	(272		)	—			—			—			(272		)
Distribution to holders of noncontrolling interest	—			—			(7		)	—			(7		)
Financing activities with affiliates, net	275			746			78			(1,099		)	—
Other, net	(2		)	—			—			—			(2		)
Net increase (decrease) cash provided by (used in) financing activities	1			746			65			(1,099		)	(287		)

Net increase (decrease) in cash and cash equivalents	3			318			(274		)	—			47
Cash and cash equivalents at beginning of period	16			842			1,777			—			2,635
Cash and cash equivalents at end of period	$	19		$	1,160		$	1,503		$	—		$	2,682

	Three months ended March 31, 2014
	Parent Guarantor			Subsidiary Issuer			Other Subsidiaries			Consolidating adjustments			Consolidated

Cash flows from operating activities	$	10		$	(128	)	$	254		$	—		$	136

Cash flows from investing activities
Capital expenditures	—			—			(1,131		)	—			(1,131		)
Proceeds from disposal of assets, net	—			—			91			—			91
Proceeds from disposal of assets in discontinued operations, net	—			—			14			—			14
Investing activities with affiliates, net	—			(737		)	62			675			—
Other, net	—			—			(12		)	—			(12		)
Net cash used in investing activities	—			(737		)	(976		)	675			(1,038		)

Cash flows from financing activities
Repayments of debt	—			—			(237		)	—			(237		)
Proceeds from restricted cash investments	—			—			107			—			107
Deposits to restricted cash investments	—			—			(20		)	—			(20		)
Distribution of qualifying additional paid-in capital	(202		)	—			—			—			(202		)
Financing activities with affiliates, net	217			(42		)	500			(675		)	—
Other, net	(2		)	—			—			—			(2		)
Net increase (decrease) cash provided by (used in) financing activities	13			(42		)	350			(675		)	(354		)

Net increase (decrease) in cash and cash equivalents	23			(907		)	(372		)	—			(1,256		)
Cash and cash equivalents at beginning of period	4			1,617			1,622			—			3,243
Cash and cash equivalents at end of period	$	27		$	710		$	1,250		$	—		$	1,987

Subsequent Events	3 Months Ended
Subsequent Events	Mar. 31, 2015
Subsequent Events
Subsequent Events	Note 18—Subsequent Events Assets held for sale—Subsequent to March 31, 2015, in connection with our strategy to reduce our exposure to lower-specification drilling units, we committed to a plan to sell for scrap value the Ultra-Deepwater Floater GSF Explorer along with related equipment. As a result, in the three months ending June 30, 2015, we expect to recognize a loss, ranging from $100 million to $120 million, net of tax, associated with the impairment of these assets. After consideration of the impairment, the remaining aggregate carrying amount of the reclassified rig and related equipment was approximately $5 million to $20 million.

Significant Accounting Policies (Policies)	3 Months Ended
Significant Accounting Policies (Policies)	Mar. 31, 2015
Significant Accounting Policies
Presentation	Presentation—We have prepared our accompanying unaudited condensed consolidated financial statements in accordance with accounting principles generally accepted in the U.S. for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X of the U.S. Securities and Exchange Commission (“SEC”). Pursuant to such rules and regulations, these financial statements do not include all disclosures required by accounting principles generally accepted in the U.S. for complete financial statements. The condensed consolidated financial statements reflect all adjustments, which are, in the opinion of management, necessary for a fair presentation of financial position, results of operations and cash flows for the interim periods. Such adjustments are considered to be of a normal recurring nature unless otherwise noted. Operating results for the three months ended March 31, 2015 are not necessarily indicative of the results that may be expected for the year ending December 31, 2015 or for any future period. The accompanying condensed consolidated financial statements and notes thereto should be read in conjunction with the audited consolidated financial statements and notes thereto as of December 31, 2014 and 2013 and for each of the three years in the period ended December 31, 2014 included in our annual report on Form 10-K filed on February 26, 2015.
Accounting estimates	Accounting estimates—To prepare financial statements in accordance with accounting principles generally accepted in the U.S., we are required to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses and the disclosures of contingent assets and liabilities. On an ongoing basis, we evaluate our estimates and assumptions, including those related to our allowance for doubtful accounts, materials and supplies obsolescence, assets held for sale, property and equipment, investments, income taxes, contingencies, share-based compensation, defined benefit pension plans and other postretirement benefits. We base our estimates and assumptions on historical experience and on various other factors we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying amounts of assets and liabilities that are not readily apparent from other sources. Actual results could differ from such estimates.
Fair value measurements	Fair value measurements—We estimate fair value at a price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants in the principal market for the asset or liability. Our valuation techniques require inputs that we categorize using a three-level hierarchy, from highest to lowest level of observable inputs, as follows: (1) significant observable inputs, including unadjusted quoted prices for identical assets or liabilities in active markets (“Level 1”), (2) significant other observable inputs, including direct or indirect market data for similar assets or liabilities in active markets or identical assets or liabilities in less active markets (“Level 2”) and (3) significant unobservable inputs, including those that require considerable judgment for which there is little or no market data (“Level 3”). When multiple input levels are required for a valuation, we categorize the entire fair value measurement according to the lowest level of input that is significant to the measurement even though we may have also utilized significant inputs that are more readily observable.
Consolidation	Consolidation—We consolidate entities in which we have a majority voting interest and entities that meet the criteria for variable interest entities for which we are deemed to be the primary beneficiary for accounting purposes. We eliminate intercompany transactions and accounts in consolidation. We apply the equity method of accounting for an investment in an entity if we have the ability to exercise significant influence over the entity that (a) does not meet the variable interest entity criteria or (b) meets the variable interest entity criteria, but for which we are not deemed to be the primary beneficiary. We apply the cost method of accounting for an investment in an entity if we do not have the ability to exercise significant influence over the unconsolidated entity. We separately present within equity on our condensed consolidated balance sheets the ownership interests attributable to parties with noncontrolling interests in our consolidated subsidiaries, and we separately present net income attributable to such parties on our condensed consolidated statements of operations. See Note 4—Variable Interest Entities and Note 15—Noncontrolling Interest.
Property and equipment	Property and equipment—The carrying amounts of our property and equipment, consisting primarily of offshore drilling rigs and related equipment, are based on our estimates, assumptions and judgments relative to capitalized costs, useful lives and salvage values of our rigs. These estimates, assumptions and judgments reflect both historical experience and expectations regarding future industry conditions and operations. At March 31, 2015, the aggregate carrying amount of our property and equipment represented approximately 76 percent of our total assets. We compute depreciation using the straight-line method after allowing for salvage values. In December 2014, we reduced the salvage values of certain drilling units due to existing market conditions. In the three months ended March 31, 2015, this change in estimate resulted in increased depreciation expense of $30 million ($28 million, or $0.08 per diluted share, net of tax). For the year ending December 31, 2015, we expect this change in estimate to result in increased depreciation expense of approximately $76 million ($73 million, net of tax).
Share-based compensation	Share-based compensation—In the three months ended March 31, 2015 and 2014, we recognized share-based compensation expense of $19 million and $28 million, respectively.
Capitalized interest	Capitalized interest—We capitalize interest costs for qualifying construction and upgrade projects. In the three months ended March 31, 2015 and 2014, we capitalized interest costs on construction work in progress of $26 million and $34 million, respectively.
Reclassifications	Reclassifications—We have made certain reclassifications to prior period amounts to conform with the current period’s presentation. Such reclassifications did not have a material effect on our condensed consolidated statement of financial position, results of operations or cash flows.
Subsequent events	Subsequent events—We evaluate subsequent events through the time of our filing on the date we issue our financial statements. See Note 18—Subsequent Events.

Variable Interest Entities (Tables)

3 Months Ended

Mar. 31, 2015

Variable Interest Entities

Carrying Amounts of Variable Interest Entities

The carrying amounts associated with our consolidated variable interest entities, after eliminating the effect of intercompany transactions, were as follows (in millions):

	March 31, 2015		December 31, 2014
Assets	$	1,257	$	1,257
Liabilities	65		74
Net carrying amount	$	1,192	$	1,183

- Definition

Tabular disclosure of the significant judgments and assumptions made in determining whether a variable interest (as defined) held by the entity requires the variable interest entity (VIE) (as defined) to be consolidated and (or) disclose information about its involvement with the VIE, individually or in aggregate (as applicable); the nature of restrictions, if any, on the consolidated VIE's assets and on the settlement of its liabilities reported by an entity in its statement of financial position, including the carrying amounts of such assets and liabilities; the nature of, and changes in, the risks associated with involvement in the VIE; how involvement with the VIE affects the entity's financial position, financial performance, and cash flows; the lack of recourse if creditors (or beneficial interest holders) of the consolidated VIE have no recourse to the general credit of the primary beneficiary (if applicable); the terms of arrangements, giving consideration to both explicit arrangements and implicit variable interests, if any, that could require the entity to provide financial support to the VIE, including events or circumstances that could expose the entity to a loss; the methodology used by the entity for determining whether or not it is the primary beneficiary of the variable interest entity; the significant factors considered and judgments made in determining that the power to direct the activities of a VIE that most significantly impact the VIE's economic performance are shared (as defined); the carrying amounts and classification of assets and liabilities of the VIE included in the statement of financial position; the entity's maximum exposure to loss, if any, as a result of its involvement with the VIE, including how the maximum exposure is determined and significant sources of the entity's exposure to the VIE; a comparison of the carrying amounts of the assets and liabilities and the entity's maximum exposure to loss; information about any liquidity arrangements, guarantees, and (or) other commitments by third parties that may affect the fair value or risk of the entity's variable interest in the VIE; whether or not the entity has provided financial support or other support (explicitly or implicitly) to the VIE that it was not previously contractually required to provide or whether the entity intends to provide that support, including the type and amount of the support and the primary reasons for providing the support; and supplemental information the entity determines necessary to provide.

+ References+ Details

Income Taxes (Tables)

3 Months Ended

Mar. 31, 2015

Income Taxes

Valuation allowance for non-current deferred tax assets

The valuation allowance for our non-current deferred tax assets was as follows (in millions):

		March 31, 2015			December 31, 2014
Valuation allowance for non-current deferred tax assets		$	395		$	340

Schedule of unrecognized tax benefits, including related interest and penalties

The liabilities related to our unrecognized tax benefits, including related interest and penalties that we recognize as a component of income tax expense, were as follows (in millions):

	March 31, 2015		December 31, 2014
Unrecognized tax benefits, excluding interest and penalties	$	271	$	265
Interest and penalties	120		120
Unrecognized tax benefits, including interest and penalties	$	391	$	385

- Definition

Tabular disclosure of tax positions taken in the tax returns filed or to be filed for which it is more likely than not that the tax position will not be sustained upon examination by taxing authorities (i.e., uncertain tax positions) and other types of income tax contingencies, including: (1) the policy on classification of interest and penalties; (2) a tabular reconciliation of the total amounts of unrecognized tax benefits at the beginning and end of the period; the total amount(s) of: (3) unrecognized tax benefits that, if recognized, would affect the effective tax rate, and (4) interest and penalties recognized in each of the income statement and balance sheet; (5) for positions for which it is reasonably possible that the total amounts unrecognized will significantly change within 12 months of the reporting date the: (i) nature of the uncertainty, (ii) nature of the event that could occur that would cause the change, and (iii) an estimate of the range of the reasonably possible change or a statement that an estimate of the range cannot be made; and (6) a description of tax years that remain subject to examination by major tax jurisdictions.

+ References+ Details

Discontinued Operations (Tables)

3 Months Ended

Mar. 31, 2015

Discontinued Operations

Summarized results income statement of discontinued operations

The summarized results of operations included in income from discontinued operations were as follows (in millions):

	Three months ended March 31,
	2015			2014
Operating revenues	$	—		$	108
Operating and maintenance expense	(1		)	(104		)
Loss on disposal of assets in discontinued operations, net	—			(10		)
Loss from discontinued operations before income tax expense	(1		)	(6		)
Income tax expense	(1		)	(2		)
Loss from discontinued operations, net of tax	$	(2	)	$	(8	)

- Definition

Tabular disclosure of disposal groups, which may include the gain (loss) recognized in the income statement and the income statement caption that includes that gain (loss), amounts of revenues and pretax profit or loss reported in discontinued operations, the classification and carrying value of the assets and liabilities comprising the disposal group, and the segment in which the disposal group was reported. Also may include the amount of adjustments to amounts previously reported in discontinued operations such as resolution of contingencies arising from the disposal transaction or the operations of the component prior to disposal.

+ References+ Details

Earnings Per Share (Tables)

3 Months Ended

Mar. 31, 2015

Earnings (Loss) Per Share

Earnings (Loss) Per Share

The numerator and denominator used for the computation of basic and diluted per share earnings (loss) from continuing operations were as follows (in millions, except per share data):

	Three months ended March 31,
	2015						2014
	Basic			Diluted			Basic			Diluted
Numerator for earnings (loss) per share
Income (loss) from continuing operations attributable to controlling interest	$	(481	)	$	(481	)	$	464		$	464
Undistributed earnings allocable to participating securities	—			—			(4		)	(4		)
Income (loss) from continuing operations available to shareholders	$	(481	)	$	(481	)	$	460		$	460

Denominator for earnings (loss) per share
Weighted-average shares outstanding	363			363			361			361
Effect of stock options and other share-based awards	—			—			—			—
Weighted-average shares for per share calculation	363			363			361			361

Per share earnings (loss) from continuing operations	$	(1.32	)	$	(1.32	)	$	1.27		$	1.27

Drilling Fleet (Tables)

3 Months Ended

Mar. 31, 2015

Drilling Fleet

Changes in our construction work in progress, including capital expenditures and capitalized interest

For the three months ended March 31, 2015 and 2014, the changes in our construction work in progress, including capital expenditures and capitalized interest, were as follows (in millions):

	Three months ended March 31,
	2015			2014
Construction work in progress, at beginning of period	$	2,451		$	2,710

Newbuild construction program
Deepwater Invictus (a) (b)	—			442
Deepwater Asgard (a) (b)	—			230
Deepwater Thalassa (c)	25			32
Deepwater Proteus (c)	9			6
Deepwater Conqueror (d)	18			80
Deepwater Pontus (c)	18			79
Deepwater Poseidon (c)	6			24
Ultra-Deepwater drillship TBN1 (e)	2			27
Transocean Cassiopeia (f)	1			1
Ultra-Deepwater drillship TBN2 (e)	—			27
Transocean Centaurus (f)	1			1
Transocean Cepheus (f)	1			1
Transocean Cetus (f)	1			1
Transocean Circinus (f)	1			1
Other construction projects and capital additions	118			179
Total capital expenditures	201			1,131
Changes in accrued capital expenditures	(22		)	(48		)

Property and equipment placed into service
Other property and equipment	(91		)	(178		)
Construction work in progress, at end of period	$	2,539		$	3,615

(a)

The accumulated construction costs of this rig are no longer included in construction work in progress, as the construction project had been completed as of March 31, 2015.

(b)

(c)

(d)

(e)

(f)

Debt (Tables)

3 Months Ended

Mar. 31, 2015

Debt

Debt, net of unamortized discounts, premiums and fair value adjustments

Debt, net of unamortized discounts, premiums and fair value adjustments, was comprised of the following (in millions):

	March 31, 2015		December 31, 2014
4.95% Senior Notes due November 2015 (a)	$	896	$	898
5.05% Senior Notes due December 2016 (a)	1,000		999
2.5% Senior Notes due October 2017 (a)	749		748
Eksportfinans Loans due January 2018	288		369
6.00% Senior Notes due March 2018 (a)	1,004		1,001
7.375% Senior Notes due April 2018 (a)	247		247
6.50% Senior Notes due November 2020 (a)	921		911
6.375% Senior Notes due December 2021 (a)	1,199		1,199
3.8% Senior Notes due October 2022 (a)	746		745
7.45% Notes due April 2027 (a)	97		97
8% Debentures due April 2027 (a)	57		57
7% Notes due June 2028	309		309
Capital lease contract due August 2029	609		615
7.5% Notes due April 2031 (a)	599		598
6.80% Senior Notes due March 2038 (a)	999		999
7.35% Senior Notes due December 2041 (a)	300		300
Total debt	10,020		10,092
Less debt due within one year
4.95% Senior Notes due November 2015 (a)	896		898
Eksportfinans Loans due January 2018	106		114
Capital lease contract due August 2029	22		21
Total debt due within one year	1,024		1,033
Total long-term debt	$	8,996	$	9,059

(a)

Scheduled maturities of debt

At March 31, 2015, the scheduled maturities of our debt were as follows (in millions):

Twelve months ending March 31,
2016	$	1,022
2017	1,131
2018	1,858
2019	277
2020	33
Thereafter	5,675
Total debt, excluding unamortized discounts, premiums and fair value adjustments	9,996
Total unamortized discounts, premiums and fair value adjustments, net	24
Total debt	$	10,020

Derivatives and Hedging (Tables)

3 Months Ended

Mar. 31, 2015

Derivatives designated as hedging instruments

Schedule of aggregate notional amounts and the weighted average interest rates associated with derivatives

	Pay					Receive
	Aggregate notional amount		Fixed or variable rate	Weighted average rate		Aggregate notional amount		Fixed or variable rate	Weighted average rate
Interest rate swaps, fair value hedge	$	1,500	Variable	4.69	%	$	1,500	Fixed	6.25	%

Derivatives designated as hedging instruments | Interest rate swaps

Derivatives designated as hedging instruments

Schedule of balance sheet classification and aggregate carrying amount, measured at fair value

The balance sheet classification and aggregate carrying amount of our derivatives designated as hedging instruments, measured at fair value, were as follows (in millions):

		March 31,		December 31,
	Balance sheet classification	2015		2014
Interest rate swaps, fair value hedges	Other current assets	$	6	$	4
Interest rate swaps, fair value hedges	Other assets	27		11

- Definition

Tabular disclosure of pertinent information about a derivative or group of derivatives on a disaggregated basis, such as for individual instruments, or small groups of similar instruments. May include a combination of the type of instrument, risks being hedged, notional amount, hedge designation, related hedged item, inception date, maturity date, or other relevant item.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 25

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41678-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41620-113959

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579240-113959

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41641-113959

Reference 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41638-113959

Reference 9: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959

Reference 10: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959

Reference 11: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(n)(2))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Postemployment Benefit Plans (Tables)

3 Months Ended

Mar. 31, 2015

Postemployment Benefit Plans

Net Periodic Benefit Costs Before Tax, and funding contributions

The components of net periodic benefit costs, before tax, and funding contributions for these plans were as follows (in millions):

	Three months ended March 31, 2015											Three months ended March 31, 2014
	U.S. Plans			Non-U.S. Plans			OPEB Plans		Total			U.S. Plans			Non-U.S. Plans			OPEB Plans		Total
Net periodic benefit costs
Service cost	$	1		$	7		$	—	$	8		$	11		$	8		$	—	$	19
Interest cost	16			5			1		22			17			6			1		24
Expected return on plan assets	(22		)	(6		)	—		(28		)	(19		)	(7		)	—		(26		)
Actuarial losses, net	3			2			—		5			5			1			—		6
Net periodic benefit costs	$	(2	)	$	8		$	1	$	7		$	14		$	8		$	1	$	23

Funding contributions	$	—		$	9		$	2	$	11		$	1		$	9		$	—	$	10

Shareholders' Equity (Tables)

3 Months Ended

Mar. 31, 2015

Shareholders' Equity

Changes in accumulated other comprehensive loss

The changes in accumulated other comprehensive loss, presented net of tax, were as follows (in millions):

	Three months ended March 31, 2015								Three months ended March 31, 2014
	Defined benefit pension plans			Derivative instruments		Total			Defined benefit pension plans			Derivative instruments			Total
Balance, beginning of period	$	(404	)	$	—	$	(404	)	$	(264	)	$	2		$	(262	)
Other comprehensive loss before reclassifications	(11		)	—		(11		)	(5		)	—			(5		)
Reclassifications to net income	1			—		1			6			(2		)	4
Other comprehensive income (loss), net	(10		)	—		(10		)	1			(2		)	(1		)
Balance, end of period	$	(414	)	$	—	$	(414	)	$	(263	)	$	—		$	(263	)

Schedule of significant reclassifications from accumulated other comprehensive income to net income

Significant reclassifications from accumulated other comprehensive income to net income included the following (in millions):

		Three months ended March 31,
	Statement of operations classification	2015			2014
Defined benefit pension plans
Actuarial losses		$	5		$	6
Total amortization, before income taxes	Net periodic benefit costs (a)	5			6
Income tax benefit	Income tax expense	(4		)	—
Total amortization, net of income taxes		$	1		$	6

(a)

Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2015

Financial Instruments

Carrying amounts and fair values of the financial instruments

The carrying amounts and fair values of our financial instruments were as follows (in millions):

	March 31, 2015				December 31, 2014
	Carrying amount		Fair value		Carrying amount		Fair value
Cash and cash equivalents	$	2,682	$	2,682	$	2,635	$	2,635
Notes and other loans receivable	15		15		15		15
Restricted cash investments	296		309		377		394
Long-term debt, including current maturities	10,020		8,834		10,092		9,778
Derivative instruments, assets	33		33		15		15

- Definition

Tabular disclosure of the fair value of financial instruments, including financial assets and financial liabilities, and the measurements of those instruments, assets, and liabilities.

+ References+ Details

Condensed Consolidating Financial Information (Tables)

3 Months Ended

Mar. 31, 2015

Condensed Consolidating Financial Information

Schedule of condensed consolidating statement of operations

The following tables include the consolidating adjustments necessary to present the condensed financial statements on a consolidated basis (in millions):

	Three months ended March 31, 2015
	Parent Guarantor			Subsidiary Issuer			Other Subsidiaries			Consolidating adjustments		Consolidated
Operating revenues	$	—		$	—		$	2,043		$	—	$	2,043
Cost and expenses	4			2			1,415			—		1,421
Loss on impairment	—			—			(936		)	—		(936		)
Loss on disposal of assets, net	—			—			(7		)	—		(7		)
Operating loss	(4		)	(2		)	(315		)	—		(321		)

Other income (expense), net
Interest income (expense), net	—			(161		)	51			—		(110		)
Equity in earnings	(479		)	(268		)	—			747		—
Other, net	—			39			8			—		47
	(479		)	(390		)	59			747		(63		)
Loss from continuing operations before income tax expense	(483		)	(392		)	(256		)	747		(384		)
Income tax expense	—			—			83			—		83
Loss from continuing operations	(483		)	(392		)	(339		)	747		(467		)
Gain (loss) from discontinued operations, net of tax	—			1			(3		)	—		(2		)

Net loss	(483		)	(391		)	(342		)	747		(469		)
Net income attributable to noncontrolling interest	—			—			14			—		14
Net loss attributable to controlling interest	(483		)	(391		)	(356		)	747		(483		)

Other comprehensive income (loss) before income taxes	(2		)	(9		)	3			—		(8		)
Income taxes related to other comprehensive loss	—			—			(2		)	—		(2		)
Other comprehensive income (loss), net of income taxes	(2		)	(9		)	1			—		(10		)

Total comprehensive loss	(485		)	(400		)	(341		)	747		(479		)
Total comprehensive income attributable to noncontrolling interest	—			—			14			—		14
Total comprehensive loss attributable to controlling interest	$	(485	)	$	(400	)	$	(355	)	$	747	$	(493	)

	Three months ended March 31, 2014
	Parent Guarantor			Subsidiary Issuer			Other Subsidiaries			Consolidating adjustments			Consolidated
Operating revenues	$	—		$	—		$	2,343		$	(4	)	$	2,339
Cost and expenses	9			1			1,593			(4		)	1,599
Loss on impairment	—			—			(65		)	—			(65		)
Loss on disposal of assets, net	—			—			(3		)	—			(3		)
Operating income (loss)	(9		)	(1		)	682			—			672

Other income (expense), net
Interest income (expense), net	6			139			(261		)	—			(116		)
Equity in earnings	459			287			—			(746		)	—
Other, net	—			1			(3		)	—			(2		)
	465			427			(264		)	(746		)	(118		)
Income from continuing operations before income tax expense	456			426			418			(746		)	554
Income tax expense	—			—			80			—			80
Income from continuing operations	456			426			338			(746		)	474
Gain (loss) from discontinued operations, net of tax	—			4			(12		)	—			(8		)

Net Income	456			430			326			(746		)	466
Net income attributable to noncontrolling interest	—			—			10			—			10
Net income attributable to controlling interest	456			430			316			(746		)	456

Other comprehensive income (loss) before income taxes	(2		)	(6		)	7			—			(1		)
Income taxes related to other comprehensive loss	—			—			—			—			—
Other comprehensive income (loss), net of income taxes	(2		)	(6		)	7			—			(1		)

Total comprehensive income	454			424			333			(746		)	465
Total comprehensive income attributable to noncontrolling interest	—			—			10			—			10
Total comprehensive income attributable to controlling interest	$	454		$	424		$	323		$	(746	)	$	455

Schedule of condensed consolidating balance sheet

The following tables include the consolidating adjustments necessary to present the condensed financial statements on a consolidated basis (in millions):

	March 31, 2015
	Parent Guarantor		Subsidiary Issuer		Other Subsidiaries		Consolidating adjustments			Consolidated
Assets
Cash and cash equivalents	$	19	$	1,160	$	1,503	$	—		$	2,682
Other current assets	3		741		4,908		(2,491		)	3,161
Total current assets	22		1,901		6,411		(2,491		)	5,843

Property and equipment, net	—		—		20,566		—			20,566
Investment in affiliates	13,210		30,270		—		(43,480		)	—
Other assets	—		4,241		26,637		(30,182		)	696
Total assets	13,232		36,412		53,614		(76,153		)	27,105

Liabilities and equity
Debt due within one year	—		896		128		—			1,024
Other current liabilities	6		465		4,169		(2,491		)	2,149
Total current liabilities	6		1,361		4,297		(2,491		)	3,173

Long-term debt	—		22,217		16,961		(30,182		)	8,996
Other long-term liabilities	25		285		1,105		—			1,415
Total long-term liabilities	25		22,502		18,066		(30,182		)	10,411

Commitments and contingencies
Redeemable noncontrolling interest	—		—		11		—			11

Total equity	13,201		12,549		31,240		(43,480		)	13,510
Total liabilities and equity	$	13,232	$	36,412	$	53,614	$	(76,153	)	$	27,105

	December 31, 2014
	Parent Guarantor		Subsidiary Issuer		Other Subsidiaries		Consolidating adjustments			Consolidated
Assets
Cash and cash equivalents	$	16	$	842	$	1,777	$	—		$	2,635
Other current assets	12		757		5,228		(2,631		)	3,366
Total current assets	28		1,599		7,005		(2,631		)	6,001

Property and equipment, net	—		—		21,538		—			21,538
Investment in affiliates	13,952		30,925		—		(44,877		)	—
Other assets	—		3,899		25,883		(28,908		)	874
Total assets	13,980		36,423		54,426		(76,416		)	28,413

Liabilities and equity
Debt due within one year	—		898		135		—			1,033
Other current liabilities	287		473		4,608		(2,631		)	2,737
Total current liabilities	287		1,371		4,743		(2,631		)	3,770

Long-term debt	—		21,486		16,481		(28,908		)	9,059
Other long-term liabilities	22		280		1,289		—			1,591
Total long-term liabilities	22		21,766		17,770		(28,908		)	10,650

Commitments and contingencies
Redeemable noncontrolling interest	—		—		11		—			11

Total equity	13,671		13,286		31,902		(44,877		)	13,982
Total liabilities and equity	$	13,980	$	36,423	$	54,426	$	(76,416	)	$	28,413

Schedule of condensed consolidating statement of cash flows

The following tables include the consolidating adjustments necessary to present the condensed financial statements on a consolidated basis (in millions):

	Three months ended March 31, 2015
	Parent Guarantor			Subsidiary Issuer			Other Subsidiaries			Consolidating adjustments			Consolidated

Cash flows from operating activities	$	2		$	(75	)	$	599		$	—		$	526

Cash flows from investing activities
Capital expenditures	—			—			(201		)	—			(201		)
Proceeds from disposal of assets, net	—			—			7			—			7
Proceeds from disposal of assets in discontinued operations, net	—			—			2			—			2
Investing activities with affiliates, net	—			(353		)	(746		)	1,099			—
Net cash used in investing activities	—			(353		)	(938		)	1,099			(192		)

Cash flows from financing activities
Repayments of debt	—			—			(63		)	—			(63		)
Proceeds from restricted cash investments	—			—			57			—			57
Distribution of qualifying additional paid-in capital	(272		)	—			—			—			(272		)
Distribution to holders of noncontrolling interest	—			—			(7		)	—			(7		)
Financing activities with affiliates, net	275			746			78			(1,099		)	—
Other, net	(2		)	—			—			—			(2		)
Net increase (decrease) cash provided by (used in) financing activities	1			746			65			(1,099		)	(287		)

Net increase (decrease) in cash and cash equivalents	3			318			(274		)	—			47
Cash and cash equivalents at beginning of period	16			842			1,777			—			2,635
Cash and cash equivalents at end of period	$	19		$	1,160		$	1,503		$	—		$	2,682

	Three months ended March 31, 2014
	Parent Guarantor			Subsidiary Issuer			Other Subsidiaries			Consolidating adjustments			Consolidated

Cash flows from operating activities	$	10		$	(128	)	$	254		$	—		$	136

Cash flows from investing activities
Capital expenditures	—			—			(1,131		)	—			(1,131		)
Proceeds from disposal of assets, net	—			—			91			—			91
Proceeds from disposal of assets in discontinued operations, net	—			—			14			—			14
Investing activities with affiliates, net	—			(737		)	62			675			—
Other, net	—			—			(12		)	—			(12		)
Net cash used in investing activities	—			(737		)	(976		)	675			(1,038		)

Cash flows from financing activities
Repayments of debt	—			—			(237		)	—			(237		)
Proceeds from restricted cash investments	—			—			107			—			107
Deposits to restricted cash investments	—			—			(20		)	—			(20		)
Distribution of qualifying additional paid-in capital	(202		)	—			—			—			(202		)
Financing activities with affiliates, net	217			(42		)	500			(675		)	—
Other, net	(2		)	—			—			—			(2		)
Net increase (decrease) cash provided by (used in) financing activities	13			(42		)	350			(675		)	(354		)

Net increase (decrease) in cash and cash equivalents	23			(907		)	(372		)	—			(1,256		)
Cash and cash equivalents at beginning of period	4			1,617			1,622			—			3,243
Cash and cash equivalents at end of period	$	27		$	710		$	1,250		$	—		$	1,987

Business (Details) (Continuing operations)	Mar. 31, 2015 item
Continuing operations
Number of mobile offshore drilling units	66
Number of High-Specification Floaters (in drilling units)	42
Number of Midwater Floaters (in drilling units)	14
Number of High-Specification Jackups (in drilling units)	10
Number of Ultra-Deepwater drillships under construction (in drilling units)	7
Number of High-Specification Jackup under construction (in drilling units)	5

Significant Accounting Policies (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Share-based compensation expense
Share-based compensation expense	$ 19	$ 28
Capitalized interest
Capitalized interest costs on construction work in progress	26	34
Property and equipment
Property and equipment as a percentage of total assets	76.00%
Drilling rig units
Property and equipment
Increase in depreciation expense due to adjustment in salvage value	30
Increase in depreciation expense due to adjustment in salvage value, net of tax	28
Increase in depreciation expense due to adjustment in salvage value per diluted per share	$ 0.08
Increase in depreciation expense in 2015 due to adjustment in salvage value	76
Increase in depreciation expense in 2015 due to adjustment in salvage value, net of tax	$ 73

Variable Interest Entities (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Carrying amounts associated with consolidated variable interest entities
Assets	$ 1,257	$ 1,257
Liabilities	65	74
Net carrying amount	$ 1,192	$ 1,183

Impairments (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Assets held and used
Loss associated with impairment	$ 507
Loss associated with impairment, net of tax	481
Loss associated with impairment per diluted share	$ 1.34
Assets held for sale
Assets held for sale
Aggregate loss on impairment of assets held for sale	429	65
Aggregate loss on impairment of assets held for sale, net of tax	393
Aggregate loss on impairment of assets per diluted share	$ 1.07	$ 0.19
Aggregate loss on impairment of assets held for sale, tax effect		$ 0

Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Income Taxes
Annual effective tax rate (as a percent)	25.80%	15.10%
Reconciliation of the differences between the income tax expense for the entity's continuing operations computed at the Swiss holding company statutory rate and the reported provision for income taxes
Income tax expense	$ 83	$ 80
Deferred taxes
Valuation allowance for non-current deferred tax assets	395		340
Unrecognized tax benefits
Unrecognized tax benefits, excluding interest and penalties	271		265
Interest and penalties	120		120
Unrecognized tax benefits, including interest and penalties	$ 391		$ 385

Income Taxes (Details 2)	1 Months Ended	3 Months Ended				3 Months Ended
Income Taxes (Details 2)	May 31, 2013 NOK subsidiary	Mar. 31, 2015 USD ($) subsidiary jurisdiction	Mar. 31, 2015 NOK subsidiary jurisdiction	Dec. 31, 2005 USD ($)	Dec. 31, 2005 BRL	Mar. 31, 2015 Minimum	Mar. 31, 2015 Maximum	Mar. 31, 2015 Norway Tax Assessments Prior to 2012 USD ($) subsidiary advisor	Mar. 31, 2015 Norway Tax Assessments Prior to 2012 NOK subsidiary advisor	Mar. 31, 2015 Norway Tax Assessments 2012 USD ($) subsidiary advisor	Mar. 31, 2015 Norway Tax Assessments 2012 NOK	Mar. 31, 2015 2010 and 2011 federal income tax returns USD ($)	May 19, 2014 Brazil Tax Assessments 2009 And 2010 USD ($)	May 19, 2014 Brazil Tax Assessments 2009 And 2010 BRL
Income Tax Examination
Range of tax returns are subject to examination						3 years	6 years
Number of jurisdictions with extensions beyond statute of limitations		2	2
Maximum number of years agreed to extensions beyond the statute of limitations		20 years	20 years
Net adjustments of additional taxes, excluding interest and penalties, related to assessments on 2010 and 2011 U.S. federal income tax returns												$ 290,000,000
Norway tax assessment due to migration of subsidiary, including interest								85,000,000	684,000,000
Norway tax assessment due to 2001 dividend payment, including interest								51,000,000	412,000,000
Norway tax assessment due to foreign exchange deductions and dividend withholding taxes, including interest								5,000,000	43,000,000
Number of subsidiaries against which notification of criminal charges are issued								2	2	2	2
Number of employees of former external advisors indicted								2	2	2	2
Financial claim issued by the Norwegian authorities supplementing the criminal indictments										223,000,000	1,800,000,000
Financial claim dropped by the Norwegian authorities	1,800,000,000
Number of subsidiaries against which notification of criminal charges are dropped	1
Criminal penalties to be assessed by court in addition to civil tax penalties		29,000,000	230,000,000
Number of subsidiaries against which criminal penalties in addition to civil tax penalties will be assessed		3	3
Brazil tax assessment for income tax returns				$ 226,000,000	723,000,000								$ 39,000,000	126,000,000
Percentage of penalty and interest to be assessed by Brazil tax authorities				75.00%	75.00%								75.00%	75.00%

Discontinued Operations (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Nov. 30, 2012 item
Summarized results of discontinued operations
Operating revenues		$ 108
Operating and maintenance expense	(1)	(104)
Gain (loss) on disposal of assets in discontinued operations, net		(10)
Loss from discontinued operations before income tax expense	(1)	(6)
Income tax expense	(1)	(2)
Loss from discontinued operations, net of tax	(2)	(8)
Summarized results of Discontinued Operations
Proceeds from disposal of assets, net	7	91
Aggregate gain (loss) on disposal of assets, net	(7)	(3)
Proceeds from disposal of discontinued operations, net	2	14
Shelf Drilling Holdings, Ltd
Summarized results of Discontinued Operations
Number of Drilling Units Sold				38
Proceeds from disposal of assets, net	2	3
Maximum financial support	125
Letters of credit issued under committed and uncommitted credit lines	79		91	113
Maximum additional financial support, excluding parent guarantees	65
Shelf Drilling Holdings, Ltd \| Minimum
Summarized results of Discontinued Operations
Period for which Standard Jackups are agreed to be operated under operating agreements	9 months
Shelf Drilling Holdings, Ltd \| Maximum
Summarized results of Discontinued Operations
Period for which Standard Jackups are agreed to be operated under operating agreements	27 months
ADTI
Summarized results of discontinued operations
Gain (loss) on disposal of assets in discontinued operations, net		(11)
Summarized results of Discontinued Operations
Aggregate loss on sale of assets per diluted share (in dollars per share)		$ (0.03)
Proceeds from disposal of discontinued operations, net		11
Aggregate gain (loss) on disposal of assets, tax effect		0
Fixed interest percentage on working capital line of credit to buyer	8.30%
Borrowings outstanding under working capital line of credit to buyer	15		15
Working capital line of credit to the buyer		15
Disposal of assets unrelated to rig sales
Summarized results of Discontinued Operations
Recognized aggregate net gain (loss) on disposal of assets unrelated to disposition of rigs		1
Aggregate gain (loss) on disposal of assets, tax effect		$ 0

Earnings Per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Numerator for earnings (loss) per share, basic
Income (loss) from continuing operations attributable to controlling interest	$ (481)	$ 464
Undistributed earnings allocable to participating securities		(4)
Income (loss) from continuing operations available to shareholders	(481)	460
Denominator for earnings (loss) per share, basic
Weighted-average shares outstanding	363	361
Weighted-average shares for per share calculation, basic	363	361
Per share earnings (loss) from continuing operations, basic	$ (1.32)	$ 1.27
Numerator for earnings (loss) per share, diluted
Income (loss) from continuing operations attributable to controlling interest	(481)	464
Undistributed earnings allocable to participating securities		(4)
Income (loss) from continuing operations available to shareholders	$ (481)	$ 460
Denominator for earnings (loss) per share, diluted
Weighted-average shares outstanding	363	361
Weighted-average shares for per share calculation, diluted	363	361
Per share earnings (loss) from continuing operations, diluted	$ (1.32)	$ 1.27
Share-based awards
Anti-dilutive securities
Share-based awards excluded from earnings per share calculation (in shares)	5.0	2.3

Drilling Fleet (Details) (USD $)
In Millions, unless otherwise specified

3 Months Ended

1 Months Ended

3 Months Ended

Mar. 31, 2015

item

Mar. 31, 2014

Oct. 31, 2011

Aker Drilling

Mar. 31, 2014

Deepwater Invictus

Mar. 31, 2014

Deepwater Asgard

Mar. 31, 2015

Deepwater Thalassa

Mar. 31, 2014

Deepwater Thalassa

Mar. 31, 2015

Deepwater Proteus

Mar. 31, 2014

Deepwater Proteus

Mar. 31, 2015

Deepwater Conqueror

Mar. 31, 2014

Deepwater Conqueror

Mar. 31, 2015

Deepwater Pontus

Mar. 31, 2014

Deepwater Pontus

Mar. 31, 2015

Deepwater Poseidon

Mar. 31, 2014

Deepwater Poseidon

Mar. 31, 2015

Ultra-Deepwater drillship TBN1

Mar. 31, 2014

Ultra-Deepwater drillship TBN1

Mar. 31, 2015

Transocean Cassiopeia

Mar. 31, 2014

Transocean Cassiopeia

Mar. 31, 2014

Ultra-Deepwater drillship TBN2

Mar. 31, 2015

Transocean Centaurus

Mar. 31, 2014

Transocean Centaurus

Mar. 31, 2015

Transocean Cepheus

Mar. 31, 2014

Transocean Cepheus

Mar. 31, 2015

Transocean Cetus

Mar. 31, 2014

Transocean Cetus

Mar. 31, 2015

Transocean Circinus

Mar. 31, 2014

Transocean Circinus

Mar. 31, 2015

Other construction projects and capital additions

Mar. 31, 2014

Other construction projects and capital additions

Mar. 31, 2015

Other property and equipment

Mar. 31, 2014

Other property and equipment

Changes in construction work in progress, including capital expenditures and other capital additions, such as capitalized interest

Construction work in progress, at beginning of period

$ 2,451

$ 2,710

Total capital expenditures

201

1,131

442

^[1],[2]

230

^[1],[2]

^[3]

^[4]

^[3]

^[5]

^[6]

^[5]

^[6]

118

179

Changes in accrued capital expenditures

(22)

(48)

Acquisition of construction work in progress

272

Property and equipment placed into service

(91)

(178)

Construction work in progress, at end of period

$ 2,539

$ 3,615

Number of High Specification Jackups under construction

Number of Ultra-Deepwater Floaters under construction

[1]	The accumulated construction costs of this rig are no longer included in construction work in progress, as the construction project had been completed as of March 31, 2015.
[2]	The Ultra-Deepwater drillships Deepwater Invictus and Deepwater Asgard, commenced operations in July 2014 and August 2014, respectively. The total carrying amount included capitalized costs of $272 million, representing the estimated fair value of construction in progress acquired in connection with our acquisition of Aker Drilling ASA in October 2011.
[3]	Deepwater Thalassa, Deepwater Proteus, Deepwater Pontus and Deepwater Poseidon, four newbuild Ultra-Deepwater drillships under construction at the Daewoo Shipbuilding & Marine Engineering Co. Ltd. shipyard in Korea, are expected to commence operations in the first quarter of 2016, the third quarter of 2016, the first quarter of 2017 and the second quarter of 2017, respectively.
[4]	Deepwater Conqueror, a newbuild UltraDeepwater drillship under construction at the Daewoo Shipbuilding & Marine Engineering Co. Ltd. shipyard in Korea, is expected to commence operations in the fourth quarter of 2016.
[5]	Our two unnamed dynamically positioned UltraDeepwater drillships under construction at the Jurong Shipyard PTE Ltd. in Singapore do not yet have drilling contracts and are expected to be delivered in the second quarter of 2017 and the first quarter of 2018, respectively.
[6]	Transocean Cassiopeia, Transocean Centaurus, Transocean Cepheus, Transocean Cetus and Transocean Circinus, five Keppel FELS Super B 400 Bigfoot class design newbuild HighSpecification Jackups under construction at Keppel FELS’ shipyard in Singapore do not yet have drilling contracts and are expected to be delivered in the first quarter of 2018, the third quarter of 2018, the first quarter of 2019, the third quarter of 2019 and the first quarter of 2020, respectively. These delivery expectations reflect our decision to delay delivery in consideration of existing market conditions.

Drilling Fleet (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Dispositions
Net cash proceeds from sale of assets	$ 7	$ 91
Loss on disposal of assets, net	(7)	(3)
Aggregate carrying amount of assets held for sale			25
Assets of discontinued operations			2
Sale of Deepwater Floater Discoverer Seven Seas and the Midwater Floater C. Kirk Rhein, Jr. along with related equipment
Dispositions
Net cash proceeds from sale of assets	5
Assets held for sale of Ultra-Deepwater Floater Deepwater Expedition, the Deepwater Floaters, Sedco 707, Sedco 710 Sovereign Explorer and Transocean Rather and the Midwater Floaters, Falcon 100, GSF Aleutian Key, GSF Arctic I, GSF Arctic III, J.W. McLean, Sedco 601, Sedco 700, Sedneth 701 and Transocean Legend, along with related equipment
Dispositions
Aggregate carrying amount of assets held for sale	23
Assets Held For Sale Deepwater Floaters Discoverer Seven Seas, Sedco 710 and Sovereign Explorer and the Midwater Floaters Sedneth 701, C. Kirk Rhein, Jr, Falcon 100, GSF Arctic I, J.W. McLean, Sedco 601 and Sedco 700 with related equipment
Dispositions
Aggregate carrying amount of assets held for sale			23
Sale of other assets
Dispositions
Net cash proceeds from sale of assets	2	8
Loss on disposal of assets, net	(9)	(3)
Sale of the High Specification Jackup GSF Monitor along with related equipment
Dispositions
Net cash proceeds from sale of assets		$ 83

Debt (Details)								3 Months Ended	0 Months Ended					3 Months Ended													3 Months Ended	0 Months Ended																				3 Months Ended	0 Months Ended	3 Months Ended			3 Months Ended
Debt (Details)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Mar. 31, 2015 4.95% Senior Notes due November 2015 USD ($)	Dec. 31, 2014 4.95% Senior Notes due November 2015 USD ($)	Mar. 31, 2015 5.05% Senior Notes due December 2016 USD ($)	Dec. 31, 2014 5.05% Senior Notes due December 2016 USD ($)	Dec. 31, 2011 5.05% Senior Notes due December 2016 USD ($)	Mar. 31, 2015 5.05% Senior Notes due December 2016 Forecast	Apr. 15, 2015 2.5% Senior Notes due October 2017	Apr. 15, 2015 2.5% Senior Notes due October 2017	Mar. 31, 2015 2.5% Senior Notes due October 2017 USD ($)	Dec. 31, 2014 2.5% Senior Notes due October 2017 USD ($)	Sep. 30, 2012 2.5% Senior Notes due October 2017 USD ($)	Mar. 31, 2015 Eksportfinans Loans due January 2018 USD ($) subsidiary	Mar. 31, 2015 Eksportfinans Loans due January 2018 NOK subsidiary	Dec. 31, 2014 Eksportfinans Loans due January 2018 USD ($)	Dec. 31, 2014 Eksportfinans Loans due January 2018 NOK	Mar. 31, 2015 6.00% Senior Notes due March 2018 USD ($)	Dec. 31, 2014 6.00% Senior Notes due March 2018 USD ($)	Mar. 31, 2015 7.375% Senior Notes due April 2018 USD ($)	Dec. 31, 2014 7.375% Senior Notes due April 2018 USD ($)	Mar. 31, 2015 6.50% Senior Notes due November 2020 USD ($)	Dec. 31, 2014 6.50% Senior Notes due November 2020 USD ($)	Mar. 31, 2015 6.375% Senior Notes due December 2021 USD ($)	Dec. 31, 2014 6.375% Senior Notes due December 2021 USD ($)	Dec. 31, 2011 6.375% Senior Notes due December 2021 USD ($)	Mar. 31, 2015 6.375% Senior Notes due December 2021 Forecast	Apr. 15, 2015 3.8% Senior Notes due October 2022	Apr. 15, 2015 3.8% Senior Notes due October 2022	Mar. 31, 2015 3.8% Senior Notes due October 2022 USD ($)	Dec. 31, 2014 3.8% Senior Notes due October 2022 USD ($)	Sep. 30, 2012 3.8% Senior Notes due October 2022 USD ($)	Mar. 31, 2015 7.45% Notes due April 2027 USD ($)	Dec. 31, 2014 7.45% Notes due April 2027 USD ($)	Mar. 31, 2015 8% Debentures due April 2027 USD ($)	Dec. 31, 2014 8% Debentures due April 2027 USD ($)	Mar. 31, 2015 7% Notes due June 2028 USD ($)	Dec. 31, 2014 7% Notes due June 2028 USD ($)	Mar. 31, 2015 Capital lease contract due August 2029 USD ($)	Dec. 31, 2014 Capital lease contract due August 2029 USD ($)	Mar. 31, 2015 7.5% Notes due April 2031 USD ($)	Dec. 31, 2014 7.5% Notes due April 2031 USD ($)	Mar. 31, 2015 6.80% Senior Notes due March 2038 USD ($)	Dec. 31, 2014 6.80% Senior Notes due March 2038 USD ($)	Mar. 31, 2015 7.35% Senior Notes due December 2041 USD ($)	Dec. 31, 2014 7.35% Senior Notes due December 2041 USD ($)	Dec. 31, 2011 7.35% Senior Notes due December 2041 USD ($)	Mar. 31, 2015 7.35% Senior Notes due December 2041 Forecast	Mar. 31, 2015 Five-Year Revolving Credit Facility USD ($)	Mar. 18, 2015 Five-Year Revolving Credit Facility	Mar. 31, 2015 Five-Year Revolving Credit Facility USD ($)	Mar. 31, 2015 Five-Year Revolving Credit Facility Base Rate	Mar. 31, 2015 Five-Year Revolving Credit Facility Minimum	Mar. 31, 2015 Five-Year Revolving Credit Facility Minimum Adjusted LIBOR	Mar. 31, 2015 Five-Year Revolving Credit Facility Maximum	Mar. 31, 2015 Five-Year Revolving Credit Facility Maximum Adjusted LIBOR	Mar. 31, 2015 Transocean Ltd. and Subsidiaries
Long-term debt by current and noncurrent
Total debt	$ 10,020,000,000	$ 10,092,000,000	$ 896,000,000	$ 898,000,000	$ 1,000,000,000	$ 999,000,000					$ 749,000,000	$ 748,000,000		$ 288,000,000		$ 369,000,000		$ 1,004,000,000	$ 1,001,000,000	$ 247,000,000	$ 247,000,000	$ 921,000,000	$ 911,000,000	$ 1,199,000,000	$ 1,199,000,000					$ 746,000,000	$ 745,000,000		$ 97,000,000	$ 97,000,000	$ 57,000,000	$ 57,000,000	$ 309,000,000	$ 309,000,000	$ 609,000,000	$ 615,000,000	$ 599,000,000	$ 598,000,000	$ 999,000,000	$ 999,000,000	$ 300,000,000	$ 300,000,000
Debt due within one year	1,024,000,000	1,033,000,000	896,000,000	898,000,000										106,000,000		114,000,000																							22,000,000	21,000,000
Long-term debt	8,996,000,000	9,059,000,000
Debt instrument interest rate stated percentage			4.95%		5.05%			5.55%		3.00%	2.50%							6.00%		7.375%		6.50%		6.375%			6.875%		4.30%	3.80%			7.45%		8.00%		7.00%				7.50%		6.80%		7.35%			7.85%
Percentage ownership interest in Transocean Inc. by Transocean Ltd.																																																									100.00%
Credit facility term																																																			5 years
Borrowing capacity, maximum																																																	3,000,000,000		3,000,000,000
Debt instrument face value							1,000,000,000						750,000,000													1,200,000,000						750,000,000															300,000,000
Spread on variable rate basis (as a percent)																																																	1.75%	1.50%				1.125%		2.00%
Percentage reduction to the calculated variable rate																																																				1.00%
Commitment fee percentage at period end																																																	0.275%	0.225%			0.15%		0.35%
Interest rate increase								0.50%	0.50%																		0.50%	0.50%																				0.50%
Debt to tangible capitalization ratio																																																					0.6		1.0
Credit facility amount outstanding																																																	0		0
Credit facility available borrowing capacity																																																	3,000,000,000		3,000,000,000
Letters of credit issued and outstanding																																																	0		0
Aggregate principal amount outstanding	9,996,000,000				1,000,000,000						750,000,000			290,000,000	2,300,000,000	370,000,000	2,800,000,000							1,200,000,000						750,000,000															300,000,000
Number of wholly-owned subsidiaries which are obligors to debt instrument														1	1
Restricted investments used as security for debt instruments														$ 290,000,000	2,300,000,000	$ 370,000,000	2,800,000,000

Debt (Details 2) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Scheduled maturities of debt
2016	$ 1,022
2017	1,131
2018	1,858
2019	277
2020	33
Thereafter	5,675
Total debt, excluding unamortized discounts, premiums and fair value adjustments	9,996
Total unamortized discounts, premiums and fair value adjustments, net	24
Total debt	$ 10,020	$ 10,092

Derivatives and Hedging (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
6.00% Senior Notes due March 2018
Derivatives and Hedging
Interest rate on notes hedged to reduce exposure to changes in fair value (as a percent)	6.00%
6.50% Senior Notes due November 2020
Derivatives and Hedging
Interest rate on notes hedged to reduce exposure to changes in fair value (as a percent)	6.50%
4.95% Senior Notes due November 2015
Derivatives and Hedging
Interest rate on notes hedged to reduce exposure to changes in fair value (as a percent)	4.95%
Derivatives designated as hedging instruments \| Interest rate swaps \| Fair value hedges \| Other current assets
Derivatives and Hedging
Derivatives at fair value	$ 6	$ 4
Derivatives designated as hedging instruments \| Interest rate swaps \| Fair value hedges \| Other assets
Derivatives and Hedging
Derivatives at fair value	27	11
Derivatives designated as hedging instruments \| Interest rate swaps \| Fair value hedges \| Pay
Derivatives and Hedging
Aggregate notional amount	1,500
Weighted average variable rate (as a percent)	4.69%
Derivatives designated as hedging instruments \| Interest rate swaps \| Fair value hedges \| Receive
Derivatives and Hedging
Aggregate notional amount	$ 1,500
Weighted average fixed rate (as a percent)	6.25%

- Definition

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References+ Details

Postemployment Benefit Plans (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015 plan	Mar. 31, 2014
Postemployment Benefit Plans
Number of other unfunded supplemental benefit plans	1
Net periodic benefit costs, before tax
Service cost	$ 8	$ 19
Interest cost	22	24
Expected return on plan assets	(28)	(26)
Actuarial losses, net	5	6
Net periodic benefit costs	7	23
Funding contributions	11	10
U.S. Plans
Net periodic benefit costs, before tax
Service cost	1	11
Interest cost	16	17
Expected return on plan assets	(22)	(19)
Actuarial losses, net	3	5
Net periodic benefit costs	(2)	14
Funding contributions		1
Non-U.S. Plans
Net periodic benefit costs, before tax
Service cost	7	8
Interest cost	5	6
Expected return on plan assets	(6)	(7)
Actuarial losses, net	2	1
Net periodic benefit costs	8	8
Funding contributions	9	9
OPEB Plans
Net periodic benefit costs, before tax
Interest cost	1	1
Net periodic benefit costs	1	1
Funding contributions	$ 2

Commitments and Contingencies (Details)				0 Months Ended							3 Months Ended				1 Months Ended							3 Months Ended			12 Months Ended						1 Months Ended
Commitments and Contingencies (Details)	Mar. 31, 2015 item	Jul. 31, 2014 Petrobras USD ($)	Jul. 31, 2014 Petrobras BRL	Sep. 04, 2014 Macondo well incident subsidiary item	Mar. 31, 2015 Macondo well incident USD ($) claim	Jan. 15, 2015 Macondo well incident bbl	Dec. 31, 2014 Macondo well incident USD ($)	Sep. 04, 2014 Macondo well incident	Jan. 03, 2013 Macondo well incident USD ($)	Apr. 22, 2010 Macondo well incident mi person	Mar. 31, 2015 Macondo well incident Wrongful death and personal injury lawsuit	Mar. 31, 2015 Macondo well incident Economic loss lawsuit	Mar. 31, 2015 Macondo well incident State and other government claims item	Mar. 31, 2015 Macondo well incident Natural Resources Damages Assessments item	Jan. 31, 2013 Macondo well incident Citizen suits under environmental statutes item	Sep. 30, 2010 Macondo well incident Federal securities claims subsidiary	Mar. 31, 2015 Macondo well incident Wreck removal USD ($)	Apr. 22, 2010 Macondo well incident Insurance coverage USD ($)	Mar. 31, 2015 Macondo well incident Contractual indemnity USD ($)	Sep. 04, 2014 Macondo well incident BP	Sep. 04, 2014 Macondo well incident Halliburton	Mar. 31, 2015 Macondo well incident Consent Decree USD ($)	Mar. 31, 2014 Macondo well incident Consent Decree USD ($)	Mar. 31, 2015 Asbestos litigation USD ($) lawsuit subsidiary plaintiff item	Dec. 31, 2004 Asbestos litigation plaintiff lawsuit	Mar. 31, 2015 Asbestos litigation Minimum subsidiary	Sep. 30, 2006 Rio de Janeiro tax assessment USD ($) subsidiary	Sep. 30, 2006 Rio de Janeiro tax assessment BRL	Dec. 31, 2010 Brazilian import license assessment USD ($)	Dec. 31, 2010 Brazilian import license assessment BRL	Oct. 31, 2007 Nigerian Cabotage Act litigation subsidiary	Mar. 31, 2015 Hazardous waste disposal sites subsidiary	Mar. 31, 2015 Retained risk USD ($)	Mar. 31, 2015 Letters of credit and surety bonds USD ($)	Dec. 31, 2014 Letters of credit and surety bonds USD ($)
Contingencies
Number of persons declared dead										11
Number of miles Deepwater Horizon was off coast of Louisiana										41
Amount of fines, recoveries and civil penalties		$ 89,000,000	283,000,000		$ 426,000,000		$ 426,000,000		$ 1,400,000,000
Amount paid for obligations under the Plea Agreement and Consent Decree including interest																						264,000,000	472,000,000
Portion of liability related to the rig explosion and fire incident recoverable from insurance					10,000,000
Number of phases of the trial completed	2
Percentage of fault assigned by the court								30												67	3
Number of bases for imposing negligence liability				3
Number of failures determined by the MDL Court				3
Number of wholly owned subsidiary that could not limit their liability under the Limitation of Liability Act				3
Number of entities that released from liability under general maritime law				2
Percentage of non-operating interest of Anadarko in the Macondo well					25.00%
Percentage of non-operating interest of MOEX in the Macondo well					10.00%
Period within which opening briefs are to be filed				30 days
Number of barrels of oil discharged during the spill determined by the court						4,000,000
Number of barrels of oil discharged during the spill, net of collected, on which penalty may be imposed						3,190,000
Number of actions or claims that were pending					1,405						9	982													21
Number of complaints that involve fatalities											9
Number of complaints that seek recovery for bodily injuries											63
Number of putative class action complaints filed alleging, among other things, economic losses as a result of environmental pollution arising out of the Macondo well incident (in lawsuits)												190
Number of state, local and foreign governments who have filed lawsuits													200
Number of Atlantic Coast states Attorneys General wanting assurances of financial responsibility for potential damages													11
Number of requests for natural resources damages assessments														11
Number of exceptions in dismissal of claims															1
Number of acquired companies as defendants in class action in U.S. District Court for the Southern District of New York																1
Percentage of asset value covered																	25.00%
Asset value covered by wreck removal insurance																	140,000,000
Number of pending separate lawsuits remained, each with a single plaintiff																								15
Number of years of litigation																								10 years
Number of plaintiffs whose litigation remains pending against subsidiaries																								8
Number of subsidiaries that were served a Notice and Demand from the Nigeria Maritime Administration and Safety Agency (NIMASA)																															3
Percentage of surcharge on the value of contracts performed in Nigeria pursuant to the Coastal and Inland Shipping (Cabotage) Act 2003 (the Cabotage Act)																															2
Insured status under excess liability insurance program																		950,000,000
Deductible amount under excess liability insurance program																		15,000,000
Amount covered by self insured layer of excess liability insurance program																		50,000,000
Amount covered by first layer of excess liability insurance program																		150,000,000
Amount covered by second layer of excess liability insurance program																		150,000,000
Amount covered by third layer of excess liability insurance program																		200,000,000
Amount covered by fourth layer of excess liability insurance program																		200,000,000
Amount covered by fifth layer of excess liability insurance program																		250,000,000
Amount agreed to indemnify and defend operator of rig																			15,000,000
Number of claimants																									769
Number of lawsuits in which case is pending against subsidiaries																								4
Number of subsidiaries against which cases are pending																										1
Number of subsidiaries involved in lawsuits arising from design, construction and refurbishment of major industrial complexes																								1
Number of lawsuits alleging personal injury from asbestos exposure for subsidiary involved in design, construction and refurbishment of major industrial complexes																								693
Estimated number of plaintiffs in lawsuits alleging personal injury from asbestos exposure for subsidiary involved in design, construction and refurbishment of major industrial complexes																								945
Insurance limits potentially available for damages in lawsuits regarding personal injury from asbestos exposure for subsidiary involved in design, construction and refurbishment of major industrial																								1,000,000,000
Tax assessment from state tax authorities																											134,000,000	428,000,000	169,000,000	539,000,000
Number of subsidiaries involved in tax assessment relating to import license																											1	1
Total amount of tax assessment from state tax authorities																													11,000,000	36,000,000
Percentage of liability for remediation and related costs																																8.00%
Number of subsidiaries ordered by California Regional Water Quality Control Board to develop testing plan for Alhambra, California site																																1
Minimum number of subsidiaries likely to be named potentially responsible party by US Environmental Protection Agency for superfund site (in counts)																																1
Aggregate value of drilling rig fleet																																	27,600,000,000
Per occurrence insurance deductible on hull and machinery																																	125,000,000
Maximum aggregate insurance deductible on hull and machinery per year																																	200,000,000
Maximum percentage of asset insured value covered by damage mitigation insurance																																	50.00%
Commercial market excess liability coverage																																	700,000,000
Per occurrence deductible on collision liability claims																																	10,000,000
Per occurrence deductible on crew personal injury and other third-party non-crew claims																																	5,000,000
Per occurrence deductible on excess liability for which risk is retained by wholly-owned insurance company																																	50,000,000
Liability loss excess amount for commercial market excess liability coverage																																	750,000,000
Additional insurance that covers expenses that would otherwise be assumed by the well owner																																	100,000,000
Outstanding letters of credit																																		305,000,000	338,000,000
Letters of credit issued under committed and uncommitted credit lines																																		79,000,000	91,000,000
Surety bonds outstanding																																		$ 6,000,000	$ 6,000,000

Shareholders' Equity (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	0 Months Ended		3 Months Ended
	Mar. 18, 2015	Mar. 19, 2014	Mar. 31, 2015 item	Mar. 31, 2014	Feb. 15, 2015 installment	Dec. 31, 2014	May 31, 2014 installment	May 31, 2013 installment
Distribution of qualifying additional paid-in capital
Cash distribution proposed in the form of additional paid-in capital (in dollars per share)					$ 0.60
Cash distribution approved in the form of additional paid-in capital (in dollars per share)							$ 3.00	$ 2.24
Number of quarterly installments (in installments)					4		4	4
Amount of installment (in dollars per share)					$ 0.15		$ 0.75	$ 0.56
Installment of dividend paid	$ 272	$ 202	$ 272	$ 202
Unpaid distribution payable						$ 272
Shares held by subsidiary
Number of subsidiaries to whom shares were issued			1
Number of shares held by subsidiary			7.6			8.7

Shareholders' Equity (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Changes in accumulated other comprehensive loss, presented net of tax
Accumulated other comprehensive loss, balance beginning of period	$ (404)	$ (262)
Other comprehensive income (loss) before reclassifications	(11)	(5)
Reclassifications to net income	1	4
Other comprehensive income (loss), net	(10)	(1)
Accumulated other comprehensive loss, balance end of period	(414)	(263)
Defined benefit pension plans
Changes in accumulated other comprehensive loss, presented net of tax
Accumulated other comprehensive loss, balance beginning of period	(404)	(264)
Other comprehensive income (loss) before reclassifications	(11)	(5)
Reclassifications to net income	1	6
Other comprehensive income (loss), net	(10)	1
Accumulated other comprehensive loss, balance end of period	(414)	(263)
Derivative instruments
Changes in accumulated other comprehensive loss, presented net of tax
Accumulated other comprehensive loss, balance beginning of period		2
Reclassifications to net income		(2)
Other comprehensive income (loss), net		$ (2)

- Definition

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References+ Details

Shareholders' Equity (Details 3) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Significant reclassifications from accumulated other comprehensive income to net income
Total amortization, before income taxes	$ (384)	$ 554
Income tax benefit	(83)	(80)
Total amortization, net of income taxes	(483)	456
Defined benefit pension plans \| Amount Reclassified from Accumulated Other Comprehensive Income
Significant reclassifications from accumulated other comprehensive income to net income
Actuarial losses	5	6
Total amortization, before income taxes	5	6
Income tax benefit	(4)
Total amortization, net of income taxes	1	6
Defined benefit pension plans \| Amount Reclassified from Accumulated Other Comprehensive Income \| Operating and maintenance costs
Significant reclassifications from accumulated other comprehensive income to net income
Total amortization, before income taxes	4	4
Defined benefit pension plans \| Amount Reclassified from Accumulated Other Comprehensive Income \| General and administrative costs
Significant reclassifications from accumulated other comprehensive income to net income
Total amortization, before income taxes	$ 1	$ 2

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 20

-Article 9

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Other Comprehensive Income

-URI http://asc.fasb.org/extlink&oid=6519514

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Net Income

-URI http://asc.fasb.org/extlink&oid=6518256

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-04.19)

-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.18)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-04.22)

-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 9: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e565-108580

Reference 10: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 19

-Article 5

+ Details

Financial Instruments (Details)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Mar. 31, 2015 Eksportfinans Loans due January 2018 USD ($)	Mar. 31, 2015 Eksportfinans Loans due January 2018 NOK	Dec. 31, 2014 Eksportfinans Loans due January 2018 USD ($)	Dec. 31, 2014 Eksportfinans Loans due January 2018 NOK	Mar. 31, 2015 Carrying amount USD ($)	Dec. 31, 2014 Carrying amount USD ($)	Mar. 31, 2015 Carrying amount Other assets USD ($)	Dec. 31, 2014 Carrying amount Other assets USD ($)	Mar. 31, 2015 Carrying amount Eksportfinans Loans due January 2018 USD ($)	Dec. 31, 2014 Carrying amount Eksportfinans Loans due January 2018 USD ($)	Mar. 31, 2015 Carrying amount Certain contingent obligations USD ($)	Dec. 31, 2014 Carrying amount Certain contingent obligations USD ($)	Mar. 31, 2015 Fair value USD ($)	Dec. 31, 2014 Fair value USD ($)	Mar. 31, 2015 Fair value Significant other observable inputs USD ($)	Dec. 31, 2014 Fair value Significant other observable inputs USD ($)	Mar. 31, 2015 Fair value Significant other observable inputs Eksportfinans Loans due January 2018 USD ($)	Dec. 31, 2014 Fair value Significant other observable inputs Eksportfinans Loans due January 2018 USD ($)
Financial instruments
Cash and cash equivalents							$ 2,682,000,000	$ 2,635,000,000							$ 2,682,000,000	$ 2,635,000,000
Notes and other loans receivable							15,000,000	15,000,000	15,000,000	15,000,000					15,000,000	15,000,000
Restricted cash investments			290,000,000	2,300,000,000	370,000,000	2,800,000,000									309,000,000	394,000,000
Restricted cash investments							296,000,000	377,000,000			288,000,000	369,000,000	8,000,000	8,000,000					301,000,000	386,000,000
Long-term debt, including current maturities							10,020,000,000	10,092,000,000							8,834,000,000	9,778,000,000
Derivative instruments, assets							33,000,000	15,000,000							33,000,000	15,000,000
Carrying amount of cash equivalents	1,800,000,000	1,700,000,000
Debt
Fixed rate debt							$ 10,000,000,000	$ 10,100,000,000									$ 8,800,000,000	$ 9,800,000,000

Condensed Consolidating Financial Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Condensed Consolidating Financial Information
Operating revenues	$ 2,043	$ 2,339
Cost and expenses	1,421	1,599
Loss on impairment	(936)	(65)
Loss on disposal of assets, net	(7)	(3)
Operating income (loss)	(321)	672
Other income (expense), net
Interest income (expense), net	(110)	(116)
Other, net	47	(2)
Total other income (expense), net	(63)	(118)
Income (loss) from continuing operations before income tax expense	(384)	554
Income tax expense	83	80
Income (loss) from continuing operations	(467)	474
Gain (loss) from discontinued operations, net of tax	(2)	(8)
Net income (loss)	(469)	466
Net loss attributable to noncontrolling interest	14	10
Net income (loss) attributable to controlling interest	(483)	456
Other comprehensive income (loss) before income taxes	(8)	(1)
Income taxes related to other comprehensive income (loss)	(2)
Other comprehensive income (loss), net of income taxes	(10)	(1)
Total comprehensive income (loss)	(479)	465
Total comprehensive income attributable to noncontrolling interest	14	10
Total comprehensive income (loss) attributable to controlling interest	(493)	455
Reportable Entity \| Parent Guarantor
Condensed Consolidating Financial Information
Cost and expenses	4	9
Operating income (loss)	(4)	(9)
Other income (expense), net
Interest income (expense), net		6
Equity in earnings	(479)	459
Total other income (expense), net	(479)	465
Income (loss) from continuing operations before income tax expense	(483)	456
Income (loss) from continuing operations	(483)	456
Net income (loss)	(483)	456
Net income (loss) attributable to controlling interest	(483)	456
Other comprehensive income (loss) before income taxes	(2)	(2)
Other comprehensive income (loss), net of income taxes	(2)	(2)
Total comprehensive income (loss)	(485)	454
Total comprehensive income (loss) attributable to controlling interest	(485)	454
Reportable Entity \| Subsidiary Issuer
Condensed Consolidating Financial Information
Cost and expenses	2	1
Operating income (loss)	(2)	(1)
Other income (expense), net
Interest income (expense), net	(161)	139
Equity in earnings	(268)	287
Other, net	39	1
Total other income (expense), net	(390)	427
Income (loss) from continuing operations before income tax expense	(392)	426
Income (loss) from continuing operations	(392)	426
Gain (loss) from discontinued operations, net of tax	1	4
Net income (loss)	(391)	430
Net income (loss) attributable to controlling interest	(391)	430
Other comprehensive income (loss) before income taxes	(9)	(6)
Other comprehensive income (loss), net of income taxes	(9)	(6)
Total comprehensive income (loss)	(400)	424
Total comprehensive income (loss) attributable to controlling interest	(400)	424
Reportable Entity \| Other Subsidiaries
Condensed Consolidating Financial Information
Operating revenues	2,043	2,343
Cost and expenses	1,415	1,593
Loss on impairment	(936)	(65)
Loss on disposal of assets, net	(7)	(3)
Operating income (loss)	(315)	682
Other income (expense), net
Interest income (expense), net	51	(261)
Other, net	8	(3)
Total other income (expense), net	59	(264)
Income (loss) from continuing operations before income tax expense	(256)	418
Income tax expense	83	80
Income (loss) from continuing operations	(339)	338
Gain (loss) from discontinued operations, net of tax	(3)	(12)
Net income (loss)	(342)	326
Net loss attributable to noncontrolling interest	14	10
Net income (loss) attributable to controlling interest	(356)	316
Other comprehensive income (loss) before income taxes	3	7
Income taxes related to other comprehensive income (loss)	(2)
Other comprehensive income (loss), net of income taxes	1	7
Total comprehensive income (loss)	(341)	333
Total comprehensive income attributable to noncontrolling interest	14	10
Total comprehensive income (loss) attributable to controlling interest	(355)	323
Consolidating adjustments
Condensed Consolidating Financial Information
Operating revenues		(4)
Cost and expenses		(4)
Other income (expense), net
Equity in earnings	747	(746)
Total other income (expense), net	747	(746)
Income (loss) from continuing operations before income tax expense	747	(746)
Income (loss) from continuing operations	747	(746)
Net income (loss)	747	(746)
Net income (loss) attributable to controlling interest	747	(746)
Total comprehensive income (loss)	747	(746)
Total comprehensive income (loss) attributable to controlling interest	$ 747	$ (746)

Condensed Consolidating Financial Information (Details 2) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Assets
Cash and cash equivalents	$ 2,682	$ 2,635	$ 1,987	$ 3,243
Other current assets	3,161	3,366
Total current assets	5,843	6,001
Property and equipment, net	20,566	21,538
Other assets	696	874
Total assets	27,105	28,413
Liabilities and equity
Debt due within one year	1,024	1,033
Other current liabilities	2,149	2,737
Total current liabilities	3,173	3,770
Long-term debt	8,996	9,059
Other long-term liabilities	1,415	1,591
Total long-term liabilities	10,411	10,650
Commitments and contingencies
Redeemable noncontrolling interest	11	11
Total equity	13,510	13,982	17,175	16,685
Total liabilities and equity	27,105	28,413
Reportable Entity \| Parent Guarantor
Assets
Cash and cash equivalents	19	16	27	4
Other current assets	3	12
Total current assets	22	28
Investment in affiliates	13,210	13,952
Total assets	13,232	13,980
Liabilities and equity
Other current liabilities	6	287
Total current liabilities	6	287
Other long-term liabilities	25	22
Total long-term liabilities	25	22
Commitments and contingencies
Total equity	13,201	13,671
Total liabilities and equity	13,232	13,980
Reportable Entity \| Subsidiary Issuer
Assets
Cash and cash equivalents	1,160	842	710	1,617
Other current assets	741	757
Total current assets	1,901	1,599
Investment in affiliates	30,270	30,925
Other assets	4,241	3,899
Total assets	36,412	36,423
Liabilities and equity
Debt due within one year	896	898
Other current liabilities	465	473
Total current liabilities	1,361	1,371
Long-term debt	22,217	21,486
Other long-term liabilities	285	280
Total long-term liabilities	22,502	21,766
Commitments and contingencies
Total equity	12,549	13,286
Total liabilities and equity	36,412	36,423
Reportable Entity \| Other Subsidiaries
Assets
Cash and cash equivalents	1,503	1,777	1,250	1,622
Other current assets	4,908	5,228
Total current assets	6,411	7,005
Property and equipment, net	20,566	21,538
Other assets	26,637	25,883
Total assets	53,614	54,426
Liabilities and equity
Debt due within one year	128	135
Other current liabilities	4,169	4,608
Total current liabilities	4,297	4,743
Long-term debt	16,961	16,481
Other long-term liabilities	1,105	1,289
Total long-term liabilities	18,066	17,770
Commitments and contingencies
Redeemable noncontrolling interest	11	11
Total equity	31,240	31,902
Total liabilities and equity	53,614	54,426
Consolidating adjustments
Assets
Other current assets	(2,491)	(2,631)
Total current assets	(2,491)	(2,631)
Investment in affiliates	(43,480)	(44,877)
Other assets	(30,182)	(28,908)
Total assets	(76,153)	(76,416)
Liabilities and equity
Other current liabilities	(2,491)	(2,631)
Total current liabilities	(2,491)	(2,631)
Long-term debt	(30,182)	(28,908)
Total long-term liabilities	(30,182)	(28,908)
Commitments and contingencies
Total equity	(43,480)	(44,877)
Total liabilities and equity	$ (76,153)	$ (76,416)

Condensed Consolidating Financial Information (Details 3) (USD $) In Millions, unless otherwise specified	0 Months Ended		3 Months Ended
	Mar. 18, 2015	Mar. 19, 2014	Mar. 31, 2015	Mar. 31, 2014
Condensed Consolidating Financial Information
Cash flows from operating activities			$ 526	$ 136
Cash flows from investing activities
Capital expenditures			(201)	(1,131)
Proceeds from disposal of assets, net			7	91
Proceeds from disposal of assets in discontinued operations, net			2	14
Other, net				(12)
Net cash used in investing activities			(192)	(1,038)
Cash flows from financing activities
Repayments of debt			(63)	(237)
Proceeds from restricted cash investments			57	107
Deposits to restricted cash investments				(20)
Distribution of qualifying additional paid-in capital	(272)	(202)	(272)	(202)
Distribution to holders of noncontrolling interest			(7)
Other, net			(2)	(2)
Net cash used in financing activities			(287)	(354)
Net increase (decrease) in cash and cash equivalents			47	(1,256)
Cash and cash equivalents at beginning of period			2,635	3,243
Cash and cash equivalents at end of period			2,682	1,987
Reportable Entity \| Parent Guarantor
Condensed Consolidating Financial Information
Cash flows from operating activities			2	10
Cash flows from financing activities
Distribution of qualifying additional paid-in capital			(272)	(202)
Financing activities with affiliates, net			275	217
Other, net			(2)	(2)
Net cash used in financing activities			1	13
Net increase (decrease) in cash and cash equivalents			3	23
Cash and cash equivalents at beginning of period			16	4
Cash and cash equivalents at end of period			19	27
Reportable Entity \| Subsidiary Issuer
Condensed Consolidating Financial Information
Cash flows from operating activities			(75)	(128)
Cash flows from investing activities
Investing activities with affiliates, net			(353)	(737)
Net cash used in investing activities			(353)	(737)
Cash flows from financing activities
Financing activities with affiliates, net			746	(42)
Net cash used in financing activities			746	(42)
Net increase (decrease) in cash and cash equivalents			318	(907)
Cash and cash equivalents at beginning of period			842	1,617
Cash and cash equivalents at end of period			1,160	710
Reportable Entity \| Other Subsidiaries
Condensed Consolidating Financial Information
Cash flows from operating activities			599	254
Cash flows from investing activities
Capital expenditures			(201)	(1,131)
Proceeds from disposal of assets, net			7	91
Proceeds from disposal of assets in discontinued operations, net			2	14
Investing activities with affiliates, net			(746)	62
Other, net				(12)
Net cash used in investing activities			(938)	(976)
Cash flows from financing activities
Repayments of debt			(63)	(237)
Proceeds from restricted cash investments			57	107
Deposits to restricted cash investments				(20)
Financing activities with affiliates, net			78	500
Distribution to holders of noncontrolling interest			(7)
Net cash used in financing activities			65	350
Net increase (decrease) in cash and cash equivalents			(274)	(372)
Cash and cash equivalents at beginning of period			1,777	1,622
Cash and cash equivalents at end of period			1,503	1,250
Consolidating adjustments
Cash flows from investing activities
Investing activities with affiliates, net			1,099	675
Net cash used in investing activities			1,099	675
Cash flows from financing activities
Financing activities with affiliates, net			(1,099)	(675)
Net cash used in financing activities			$ (1,099)	$ (675)

Subsequent Events (Details) (USD $) In Millions, unless otherwise specified		0 Months Ended		0 Months Ended
	Dec. 31, 2014	May 06, 2014 Subsequent Event Assets held for sale Of Ultra Deepwater Floater GSF Explorer with related equipment Forecast Minimum	May 06, 2014 Subsequent Event Assets held for sale Of Ultra Deepwater Floater GSF Explorer with related equipment Forecast Minimum	May 06, 2014 Subsequent Event Assets held for sale Of Ultra Deepwater Floater GSF Explorer with related equipment Forecast Maximum	May 06, 2014 Subsequent Event Assets held for sale Of Ultra Deepwater Floater GSF Explorer with related equipment Forecast Maximum
Subsequent events
Aggregate loss on impairment of assets held for sale, net of tax		$ 100		$ 120
Aggregate carrying amount of assets held for sale	$ 25		$ 5		$ 20

Noncontrolling Interest (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015
Noncontrolling interest
Dividends received eliminated in consolidation	$ 18
Transocean Partners
Noncontrolling interest
Dividends	$ 25