Receivables - Receivables (Detail) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013		Mar. 31, 2013	Dec. 31, 2012		Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011
Real estate secured:
Total receivables	$ 29,112					$ 34,956
Real estate secured	29,112	[1],[2]		32,939	[1],[2]
HSBC acquisition purchase accounting fair value adjustments	40			43
Accrued finance income	879			909
Credit loss reserve for owned receivables	(4,098)		(4,313)	(4,607)		(4,608)	(5,865)	(5,952)
Total receivables, net	25,933			29,284
First Lien [Member]
Real estate secured:
Total receivables	25,798			29,301		30,940
Credit loss reserve for owned receivables	(3,463)		(3,619)	(3,867)		(3,858)	(4,171)	(4,089)
Second Lien [Member]
Real estate secured:
Total receivables	3,314			3,638		4,016
Credit loss reserve for owned receivables	$ (635)		$ (694)	$ (740)		$ (750)	$ (779)	$ (823)

[1] At June 30, 2013 and December 31, 2012, nonaccrual real estate secured receivables held for investment include $1.2 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 June 30, 2013 and December 31, 2012, nonaccrual real estate secured receivables held for investment include $642 million 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.