Receivables Held for Sale - Summary of Activity in Receivables Held for Sale (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2013	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Receivables Held for Sale, Activity [Roll Forward]
Receivables held for sale at beginning of period	$ 6,203	$ 2,047	[1]	$ 6,203		$ 0
Lower of amortized cost or fair value adjustment on receivables held for sale		314		748		18
Carrying value of real estate secured receivables held for sale settled through short sale or transfer to REO		(243)		(711)		(264)
Change in real estate secured receivable balance, including collections		30		(249)		(307)
Transfer of real estate secured receivables into held for investment at the lower of amortized cost or fair value		(45)
Transfer of real estate secured receivables into held for sale at the lower of amortized cost or fair value		909	[2]	2,130	[2]	6,756
Receivables held for sale at end of period		860	[1]	2,047	[1]	6,203
First Mortgage [Member]
Receivables Held for Sale, Activity [Roll Forward]
Receivable sales		(2,152)		(3,127)
Mortgage Loans on Real Estate [Member]
Receivables Held for Sale, Activity [Roll Forward]
Receivables held for sale at beginning of period	3,022	2,047	[1]	3,022		0
Lower of amortized cost or fair value adjustment on receivables held for sale		314		830		(3)
Carrying value of real estate secured receivables held for sale settled through short sale or transfer to REO		(243)		(711)		(264)
Change in real estate secured receivable balance, including collections		30		(97)		2
Transfer of real estate secured receivables into held for investment at the lower of amortized cost or fair value		(45)
Transfer of real estate secured receivables into held for sale at the lower of amortized cost or fair value		909	[2]	2,130	[2]	3,287
Receivables held for sale at end of period		860	[1]	2,047	[1]	3,022
Mortgage Loans on Real Estate [Member] | First Mortgage [Member]
Receivables Held for Sale, Activity [Roll Forward]
Receivable sales		(2,152)		(3,127)
Personal non-credit card [Member]
Receivables Held for Sale, Activity [Roll Forward]
Receivables held for sale at beginning of period	3,181	0	[1]	3,181		0
Receivable sales		0		(2,947)
Lower of amortized cost or fair value adjustment on receivables held for sale	(82)	0		(82)		21
Carrying value of real estate secured receivables held for sale settled through short sale or transfer to REO		0		0		0
Change in real estate secured receivable balance, including collections		0		(152)		(309)
Transfer of real estate secured receivables into held for investment at the lower of amortized cost or fair value		0
Transfer of real estate secured receivables into held for sale at the lower of amortized cost or fair value		0	[2]	0	[2]	3,469
Receivables held for sale at end of period		$ 0	[1]	$ 0	[1]	$ 3,181

[1] The following table provides a rollforward of our valuation allowance for 2014, 2013 and 2012. At December 31, 2014, the valuation allowance is zero as the fair value of the pool of receivables held for sale at December 31, 2014 exceeds the carrying value as these receivables are carried at the lower of amortized cost or fair value. See Note 20, "Fair Value Measurements," for a discussion of the factors impacting the fair value of these receivables.

[2] The initial lower of amortized cost or fair value adjustment on receivables transferred into held for sale during 2014, 2013 and 2012 totaled $113 million, $212 million and $1,659 million, respectively.