Derivatives (Details 1) (Fair value hedges) In Millions, unless otherwise specified	1 Months Ended			1 Months Ended		3 Months Ended			3 Months Ended
	Jul. 31, 2007 Interest rate swap contracts Eurobond repaid July 2014 EUR (€)	Jul. 31, 2014 Interest rate swap contracts Eurobond repaid July 2014 EUR (€)	Aug. 31, 2010 Interest rate swap contracts Eurobond repaid July 2014 EUR (€)	Nov. 30, 2013 Interest rate swap contracts Eurobond Due 2021 EUR (€)	Jun. 30, 2014 Interest rate swap contracts Fixed rate medium term note due 2019 USD ($)	Mar. 31, 2015 Derivatives designated as hedging instruments USD ($)	Mar. 31, 2014 Derivatives designated as hedging instruments USD ($)	Mar. 31, 2015 Derivatives designated as hedging instruments Interest rate swap contracts USD ($)	Mar. 31, 2015 Derivatives designated as hedging instruments Interest rate swap contracts Interest expense USD ($)	Mar. 31, 2014 Derivatives designated as hedging instruments Interest rate swap contracts Interest expense USD ($)
Derivatives in Fair Value Hedging Relationships
Derivative notional amount	€ 400			€ 300	$ 600			$ 1,000
Term of debt instrument	7 years			8 years	5 years
Face amount	750			600	625
Termination of notional amount of fixed-to-floating interest rate swap			150
Remaining amount matured from Interest Rate Swap		250
Gain (loss) on termination of fixed-to-floating interest rate swap will be amortized over this debt's remaining life			18
Interest rate, stated percentage (as a percent)				1.875%	1.625%
Gain (Loss) on Derivative Recognized in income						6	7		6	7
Gain (Loss) on Hedged Item Recognized in Income						$ (6)	$ (7)		$ (6)	$ (7)