v2.4.0.6
Investments (Fair Value Method Investments) (Details) (USD $)
In Billions, unless otherwise specified
3 Months Ended
Jun. 30, 2012
Prepaid forward sale obligations carrying value $ 2.9
Prepaid Forward Sale Obligations [Member]
 
Equity securities held as collateral 3.5
Prepaid forward sale obligations fair value $ 3.0