Debt Securitization Notes Payable (Details) (GM Financial [Member], USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Dec. 31, 2011
Securitization notes payable [Line Items]
Total Receivables Pledged	$ 9,550
Secured Debt	8,603	6,895
Purchase accounting premium	23	43
Securitized Notes Payable	8,626	6,938
2006 Transactions [Member]
Securitization notes payable [Line Items]
Total Receivables Pledged	0
Secured Debt	0	63
Debt Instrument, Maturity Date Range, Start	January 2014
Debt Instrument, Maturity Date Range, End	January 2014
Original Note Amounts - Minimum	1,200
Original Note Amounts - Maximum	1,200
Original Weighted-Average Interest Rate - Minimum	5.40%
Original Weighted-Average Interest Rate - Maximum	5.40%
2007 Transactions [Member]
Securitization notes payable [Line Items]
Total Receivables Pledged	0
Secured Debt	0	794
Debt Instrument, Maturity Date Range, Start	April 2014
Debt Instrument, Maturity Date Range, End	March 2016
Original Note Amounts - Minimum	1,000
Original Note Amounts - Maximum	1,500
Original Weighted-Average Interest Rate - Minimum	5.30%
Original Weighted-Average Interest Rate - Maximum	5.50%
2008 Transactions [Member]
Securitization notes payable [Line Items]
Total Receivables Pledged	346
Secured Debt	124	171
Debt Instrument, Maturity Date Range, Start	October 2014
Debt Instrument, Maturity Date Range, End	April 2015
Original Note Amounts - Minimum	500
Original Note Amounts - Maximum	750
Original Weighted-Average Interest Rate - Minimum	6.00%
Original Weighted-Average Interest Rate - Maximum	10.50%
2009 Transactions [Member]
Securitization notes payable [Line Items]
Total Receivables Pledged	300
Secured Debt	221	298
Debt Instrument, Maturity Date Range, Start	January 2016
Debt Instrument, Maturity Date Range, End	July 2017
Original Note Amounts - Minimum	227
Original Note Amounts - Maximum	725
Original Weighted-Average Interest Rate - Minimum	2.70%
Original Weighted-Average Interest Rate - Maximum	7.50%
2010 Transactions [Member]
Securitization notes payable [Line Items]
Total Receivables Pledged	1,582
Secured Debt	1,395	1,756
Debt Instrument, Maturity Date Range, Start	July 2017
Debt Instrument, Maturity Date Range, End	April 2018
Original Note Amounts - Minimum	200
Original Note Amounts - Maximum	850
Original Weighted-Average Interest Rate - Minimum	2.20%
Original Weighted-Average Interest Rate - Maximum	3.80%
2011 Transactions [Member]
Securitization notes payable [Line Items]
Total Receivables Pledged	3,374
Secured Debt	3,105	3,813
Debt Instrument, Maturity Date Range, Start	July 2018
Debt Instrument, Maturity Date Range, End	March 2019
Original Note Amounts - Minimum	800
Original Note Amounts - Maximum	1,000
Original Weighted-Average Interest Rate - Minimum	2.40%
Original Weighted-Average Interest Rate - Maximum	2.90%
2012 Transactions [Member]
Securitization notes payable [Line Items]
Total Receivables Pledged	3,948
Secured Debt	3,758
Debt Instrument, Maturity Date Range, Start	June 2019
Debt Instrument, Maturity Date Range, End	November 2019
Original Note Amounts - Minimum	800
Original Note Amounts - Maximum	$ 1,200
Original Weighted-Average Interest Rate - Minimum	1.90%
Original Weighted-Average Interest Rate - Maximum	2.90%