Finance Receivables Activity in post-acquisition consumer finance receivables portfolio (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net Amount	$ 23,867		$ 23,867		$ 10,998
Consumer Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Post-Acquisition Finance Receivables, Carrying Value	17,665		17,665
Loans and Leases Receivable, Net Amount	17,665		17,665
North America [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net Amount	12,232		12,232
North America [Member] | Consumer Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Post-Acquisition Finance Receivables, Carrying Value	10,313		10,313		8,831
Loans and Leases Receivable, Net Amount	10,313	8,255	10,313	8,255
International [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net Amount	11,635		11,635
International [Member] | Consumer Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Post-Acquisition Finance Receivables, Carrying Value	7,352		7,352
Loans and Leases Receivable, Net Amount	7,352		7,352
Post-Acquisition Portfolio [Member] | Consumer Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Post-Acquisition Finance Receivables, Carrying Value					8,831
Business Combination, Acquired Receivables, Fair Value	6,378		6,378
Payments to Acquire Loans Receivable			6,330
Financing Receivable, Allowance for Credit Losses, Write-downs	(171)		(419)
Proceeds from Collection of Finance Receivables			(3,676)
Finance Receivables - Post Acquisition - Foreign Currency Translation			221
Post-Acquisition Portfolio [Member] | North America [Member] | Consumer Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Post-Acquisition Finance Receivables, Carrying Value					8,831	5,314
Payments to Acquire Loans Receivable			3,980	4,363
Financing Receivable, Allowance for Credit Losses, Write-downs	(153)	(82)	(401)	(186)
Proceeds from Collection of Finance Receivables			(2,097)	(1,236)
Post-Acquisition Portfolio [Member] | International [Member] | Consumer Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Business Combination, Acquired Receivables, Fair Value	6,378		6,378
Payments to Acquire Loans Receivable			2,350
Financing Receivable, Allowance for Credit Losses, Write-downs	(18)		(18)
Proceeds from Collection of Finance Receivables			(1,579)
Finance Receivables - Post Acquisition - Foreign Currency Translation			$ 221