Transfers of Receivables - Derivative Income and Expense (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Derivative expense/(income) related to securitization transactions [Abstract]
Derivative expense/(income)	$ (23)	$ 209
Securitization Transactions [Member]
Derivative expense/(income) related to securitization transactions [Abstract]
Derivative expense/(income)	18	(88)
Securitization Transactions [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Derivative expense/(income) related to securitization transactions [Abstract]
Derivative expense/(income)	20	(92)
Related to Variable Interest Entity - Not VIE [Member] | Securitization Transactions [Member]
Derivative expense/(income) related to securitization transactions [Abstract]
Derivative expense/(income)	(6)	3
Other, Not Variable Interest Entity Related [Member] | Securitization Transactions [Member]
Derivative expense/(income) related to securitization transactions [Abstract]
Derivative expense/(income)	$ 4	$ 1