Transfers of Receivables - Exposure Based on Fair Value of Derivative Instruments (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Securitization Transactions [Line Items]
Fair Value of Derivative Assets	$ 585	$ 1,256
Fair Value of Derivative Liabilities	506	400
Variable Interest Entity, Primary Beneficiary [Member]
Securitization Transactions [Line Items]
Fair Value of Derivative Assets	5	4
Fair Value of Derivative Liabilities	88	134
Securitization Transactions [Member]
Securitization Transactions [Line Items]
Fair Value of Derivative Assets	33	89
Fair Value of Derivative Liabilities	125	219
Securitization Transactions [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Securitization Transactions [Line Items]
Fair Value of Derivative Assets	5	4
Fair Value of Derivative Liabilities	88	134
Related to Variable Interest Entity - Not VIE [Member] | Securitization Transactions [Member]
Securitization Transactions [Line Items]
Fair Value of Derivative Assets	23	74
Fair Value of Derivative Liabilities	30	63
Other, Not Variable Interest Entity Related [Member] | Securitization Transactions [Member]
Securitization Transactions [Line Items]
Fair Value of Derivative Assets	5	11
Fair Value of Derivative Liabilities	$ 7	$ 22