Fair Value of Financial Instruments (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Financial instruments
Restricted cash investments	$ 928	$ 47
TPDI and ADDCL Credit Facilities
Financial instruments
Restricted cash investments	39	39
Aker Drilling
Financial instruments
Restricted cash investments	889
Carrying amount
Financial instruments
Cash and cash equivalents	4,017	3,394
Accounts receivable	2,049	1,653
Notes receivable and working capital loan receivable	139	115
Restricted cash investments	928	47
Long-term debt, including current maturities	12,698	10,271
Long-term debt of consolidated variable interest entities, including current maturities	838	950
Derivative instruments, assets	36	21
Derivative instruments, liabilities	38	13
Notes receivable and working capital loan receivable
Notes receivable, current	37	4
Notes receivable, noncurrent	102	111
Fair value
Financial instruments
Cash and cash equivalents	4,017	3,394
Accounts receivable	2,049	1,653
Notes receivable and working capital loan receivable	139	115
Restricted cash investments	975	47
Long-term debt, including current maturities	13,074	10,562
Long-term debt of consolidated variable interest entities, including current maturities	838	964
Derivative instruments, assets	36	21
Derivative instruments, liabilities	$ 38	$ 13

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Represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption, parenthetical disclosure or within the fair value disclosures required in the footnote disclosures to the financial statements. This item represents the aggregate carrying amount of long-term borrowings, including current and noncurrent portions, as of the balance sheet date.

+ References

No definition available.

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Represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption, parenthetical disclosure or within the fair value disclosures required in the footnote disclosures to the financial statements. This item represents the aggregate carrying amount of long-term borrowings of consolidated variable interest entities, including current and noncurrent portions, as of the balance sheet date.

+ References

No definition available.

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Represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption, parenthetical disclosure or within the fair value disclosures required in the footnote disclosures to the financial statements. This item represents an agreement for an unconditional promise by the maker to pay the Company (holder) a definite sum of money within one year from the balance sheet date (or the normal operating cycle, whichever is longer).

+ References

No definition available.

+ Details

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- Definition

Represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption, parenthetical disclosure or within the fair value disclosures required in the footnote disclosures to the financial statements. This item represents an agreement for an unconditional promise by the maker to pay the Company (holder) a definite sum of money at a future date more than one year from the balance sheet date.

+ References

No definition available.

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- Definition

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 3

-Subparagraph a, b

-Article 5

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Company may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 7

-Footnote 1

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 7, 8, 9, 10

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 8

-Footnote 2

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents derivative financial instruments which the Company is a party to as of the balance sheet date. A derivative instrument is a financial instrument or other contract with all three of the following characteristics: (a) it has (1) one or more underlyings and (2) one or more notional amounts or payment provisions or both. Those terms determine the amount of the settlement or settlements, and, in some cases, whether or not a settlement is required; (b) it requires no initial net investment or an initial net investment that is smaller than would be required for other types of contracts that would be expected to have a similar response to changes in market factors; (c) its terms require or permit net settlement, it can readily be settled net by a means outside the contract, or it provides for delivery of an asset that puts the recipient in a position not substantially different from net settlement. Notwithstanding the forgoing characteristics, loan commitments that relate to the origination of mortgage loans that will be held for sale shall be accounted for as derivative instruments by the issuer of the loan commitment (that is, the potential lender).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 10

-Subparagraph i

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 6

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 65

-Paragraph 21

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents derivative instrument obligations meeting the definition of a liability which should be reported as of the balance sheet date. A derivative instrument is a financial instrument or other contract with all three of the following characteristics: (a) it has (1) one or more underlyings and (2) one or more notional amounts or payment provisions or both. Those terms determine the amount of the settlement or settlements, and, in some cases, whether or not a settlement is required; (b) it requires no initial net investment or an initial net investment that is smaller than would be required for other types of contracts that would be expected to have a similar response to changes in market factors; (c) its terms require or permit net settlement, it can readily be settled net by a means outside the contract, or it provides for delivery of an asset that puts the recipient in a position not substantially different from net settlement. Notwithstanding the forgoing characteristics, loan commitments that relate to the origination of mortgage loans that will be held for sale shall be accounted for as derivative instruments by the issuer of the loan commitment (that is, the potential lender).

+ References

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- Definition

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

-Subparagraph b

-Article 5

+ Details

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- Definition

Cash and investments whose use in whole or in part is restricted for the long-term, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

+ References

No definition available.

+ Details

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