Derivatives and Hedging (Details 4) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Sep. 30, 2011 USD ($)	Dec. 31, 2011 Derivative not designated as hedging instruments Forward exchange contract USD ($) exchangerate	Dec. 31, 2011 Derivative not designated as hedging instruments Forward exchange contract NOK
Derivative instruments
Exchange rate		5.4005
Aggregate notional amount, pay		$ 1,120
Aggregate notional amount, receive			6,051
Loss recognized during the period	$ 78	$ 78

- Definition

The contractual rate at which a foreign currency can be purchased or sold under the terms of a foreign currency derivative contract.

+ References

No definition available.

+ Details

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- Definition

Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as an asset.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 107

-Paragraph 10

+ Details

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- Definition

Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as a liability.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 107

-Paragraph 10

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- Details

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- Definition

Amount of gain (loss) recognized in earnings in the period from the increase (decrease) in fair value of foreign currency derivatives not designated as hedging instruments.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44

+ Details

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