Receivables - Receivables (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013		Dec. 31, 2012		Mar. 31, 2012	Dec. 31, 2011
Real estate secured:
Total receivables	$ 31,930				$ 46,037
Total real estate secured	31,930	[1],[2]	32,939	[1],[2]
HSBC acquisition purchase accounting fair value adjustments	41		43
Accrued finance income	886		909
Credit loss reserve for owned receivables	(4,313)		(4,607)		(5,865)	(5,952)
Receivables, net	28,544		29,284
First Mortgage [Member]
Real estate secured:
Total receivables	28,461		29,301		37,021
Credit loss reserve for owned receivables	(3,619)		(3,867)		(4,171)	(4,089)
Second Mortgage [Member]
Real estate secured:
Total receivables	3,469		3,638		4,222
Credit loss reserve for owned receivables	$ (694)		$ (740)		$ (779)	$ (823)

[1] At March 31, 2013 and December 31, 2012, nonperforming real estate secured receivables held for investment include $2.0 billion and $2.1 billion, respectively, of TDR Loans, some of which may also be carried at fair value of the collateral less cost to sell

[2] At March 31, 2013 and December 31, 2012, nonperforming real estate secured receivables held for investment include $1.9 billion and $1.7 billion, respectively, of receivables that are carried at the lower of amortized cost or fair value of the collateral less cost to sell.