Receivables - Summary of Contractual Delinquency and Delinquency Ratio (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Financing Receivable, Modifications [Line Items]
Dollars of Delinquency	$ 6,424	$ 8,591
Delinquency Ratio	15.93%	17.93%
First Lien [Member]
Financing Receivable, Modifications [Line Items]
Dollars of Delinquency	5,967	7,605
Delinquency Ratio	17.91%	19.89%
Second Lien [Member]
Financing Receivable, Modifications [Line Items]
Dollars of Delinquency	362	500
Delinquency Ratio	9.47%	11.16%
Real estate secured [Member]
Financing Receivable, Modifications [Line Items]
Dollars of Delinquency	6,329	8,105
Delinquency Ratio	17.04%	18.98%
Personal non-credit card [Member]
Financing Receivable, Modifications [Line Items]
Dollars of Delinquency	$ 95	$ 486
Delinquency Ratio	2.98%	9.35%