Derivatives (Details 2) (Fair value hedges) In Millions, unless otherwise specified		1 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended
	Jun. 30, 2013 Interest rate swap contracts USD ($)	Jul. 31, 2007 Interest rate swap contracts Fixed rate Eurobond Due 2014 EUR (€)	Aug. 31, 2010 Interest rate swap contracts Fixed rate Eurobond Due 2014 EUR (€)	Jun. 30, 2013 Derivatives designated as hedging instruments USD ($)	Jun. 30, 2012 Derivatives designated as hedging instruments USD ($)	Jun. 30, 2013 Derivatives designated as hedging instruments USD ($)	Jun. 30, 2012 Derivatives designated as hedging instruments USD ($)	Jun. 30, 2013 Derivatives designated as hedging instruments Interest rate swap contracts Interest expense USD ($)	Jun. 30, 2012 Derivatives designated as hedging instruments Interest rate swap contracts Interest expense USD ($)	Jun. 30, 2013 Derivatives designated as hedging instruments Interest rate swap contracts Interest expense USD ($)	Jun. 30, 2012 Derivatives designated as hedging instruments Interest rate swap contracts Interest expense USD ($)
Derivatives in Fair Value Hedging Relationships
Notional amount, interest rate swaps designated as fair value hedges	$ 342	€ 400
Term of debt instrument		7 years
Face amount		750
Termination of notional amount of fixed-to-floating interest rate swap			150
Gain (loss) on termination of fixed-to-floating interest rate swap will be amortized over this debt's remaining life			18
Gain (Loss) on Derivative Recognized in income				(3)	(2)	(8)	(3)	(3)	(2)	(8)	(3)
Gain (Loss) on Hedged Item Recognized in Income				$ 3	$ 2	$ 8	$ 3	$ 3	$ 2	$ 8	$ 3