Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

+ Details

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- Definition

Average contractual rate at which a foreign currency can be purchased or sold.

+ References

No definition available.

+ Details

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- Definition

Average variable interest rate related to the group of interest rate derivatives.

+ References

No definition available.

+ Details

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- Details

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- Definition

Amount of gain (loss)recognized in the income statement from the hedging ineffectiveness of a fair value hedge.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 25

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

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

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Derivatives (Details 2-Fair Value Hedges)	3 Months Ended		9 Months Ended
Derivatives (Details 2-Fair Value Hedges)	Sep. 30, 2013 USD ($)	Sep. 30, 2012 USD ($)	Sep. 30, 2013 USD ($)	Sep. 30, 2012 USD ($)	Sep. 30, 2013 Fair Value Hedging [Member] Foreign Exchange Contract [Member] NOK	Dec. 31, 2012 Fair Value Hedging [Member] Foreign Exchange Contract [Member] NOK	Sep. 30, 2013 Notes Due 2018 [Member] Fair Value Hedging [Member] Interest Rate Contract [Member] USD ($)	Sep. 30, 2013 Debentures Due 2017 [Member] Fair Value Hedging [Member] Interest Rate Contract [Member] USD ($)	Dec. 31, 2012 Debentures Due 2017 [Member] Fair Value Hedging [Member] Interest Rate Contract [Member] USD ($)
Derivative [Line Items]
Derivative, Notional Amount					3,115,000,000	3,043,000,000	$ 300,000,000	$ 600,000,000	$ 600,000,000
Weighted-average, LIBOR-based, floating rate							4.51%	4.67%	4.70%
Derivative, Average Forward Exchange Rate					5.874	5.780
Gain (Loss) on Fair Value Hedge Ineffectiveness, Net	$ 0	$ 0	$ 0	$ 0