Hedging Derivative instruments no longer qualifying for hedge accounting (Details) (Transferred euro put and call options and settling in 2013 [Member] [Member], EUR €) In Millions, unless otherwise specified	Mar. 31, 2013
Transferred euro put and call options and settling in 2013 [Member] [Member]
Derivative [Line Items]
Notional amount of currency derivatives designated cash flow hedges	€ 71