Finance Receivables - Aging Analysis (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number Of Days After Which Finance Receivable Is Considered Past Due	any payment, including principal and interest, that has not been collected and is at least 31 days past the contractual due date
Finance Receivables Aging Analysis [Abstract]
Financing Receivables	$ 79,075	$ 75,448	$ 71,907
International Segment [Member]
Finance Receivables Aging Analysis [Abstract]
Financing Receivables	18,515	16,642
North America Segment [Member]
Finance Receivables Aging Analysis [Abstract]
Financing Receivables	60,560	58,806
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	15	13
Finance Receivables Aging Analysis [Abstract]
31-60 Days past due	669	829
61-90 Days past due	93	114
91-120 Days past due	29	30
Greater than 120 days past due	63	81
Total past due	854	1,054
Current	48,467	45,928
Financing Receivables	49,321	46,982
Consumer Portfolio Segment [Member] | International Segment [Member]
Finance Receivables Aging Analysis [Abstract]
31-60 Days past due	38	46
61-90 Days past due	17	17
91-120 Days past due	9	9
Greater than 120 days past due	27	29
Total past due	91	101
Current	9,985	8,641
Financing Receivables	10,076	8,742
Consumer Portfolio Segment [Member] | North America Segment [Member]
Finance Receivables Aging Analysis [Abstract]
31-60 Days past due	631	783
61-90 Days past due	76	97
91-120 Days past due	20	21
Greater than 120 days past due	36	52
Total past due	763	953
Current	38,482	37,287
Financing Receivables	39,245	38,240
Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	5	5
Finance Receivables Aging Analysis [Abstract]
Total past due	67	40
Current	29,687	28,426
Financing Receivables	29,754	28,466
Commercial Portfolio Segment [Member] | International Segment [Member]
Finance Receivables Aging Analysis [Abstract]
Total past due	39	11
Current	8,400	7,889
Financing Receivables	8,439	7,900
Commercial Portfolio Segment [Member] | North America Segment [Member]
Finance Receivables Aging Analysis [Abstract]
Total past due	28	29
Current	21,287	20,537
Financing Receivables	$ 21,315	$ 20,566