Receivables - Receivables (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Jun. 30, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Dec. 31, 2010
Real estate secured:
Total real estate secured	$ 33,963		$ 42,713
Personal non-credit card			5,196
Other			3
Total receivables	33,963		47,912	49,799
HSBC acquisition purchase accounting fair value adjustments	45		57
Accrued finance income	903		1,184
Credit loss reserve for owned receivables	(4,429)	(4,608)	(5,952)	(5,911)	(4,590)	(5,512)
Total receivables, net	30,482		43,201
First Lien [Member]
Real estate secured:
Total real estate secured	30,143		38,235
Total receivables	30,143		38,235
Second Lien [Member]
Real estate secured:
Total real estate secured	3,820		4,478
Total receivables	$ 3,820		$ 4,478