Receivables Held for Sale - Summary of Activity in Receivables Held for Sale (Detail) (USD $) In Millions, unless otherwise specified			3 Months Ended		9 Months Ended		3 Months Ended	9 Months Ended
	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014 Mortgage Loans on Real Estate [Member]		Sep. 30, 2014 Mortgage Loans on Real Estate [Member]		Sep. 30, 2014 First Mortgage [Member] Mortgage Loans on Real Estate [Member]	Sep. 30, 2014 First Mortgage [Member] Mortgage Loans on Real Estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Receivables held for sale at beginning of period	$ 1,840	$ 2,047	$ 1,874		$ 2,047
Real estate secured receivables sold							(272)	(1,156)
Lower of amortized cost or fair value adjustment on real estate secured receivables held for sale			94		404
Carrying value of real estate secured receivables held for sale settled through short sale or transfer to REO			(59)		(207)
Change in real estate secured receivable balance, including collections			(11)		12
Transfer of real estate secured receivables into held for investment at the lower of amortized cost or fair value					(8)	[1]
Transfer of real estate secured receivables into held for sale at the lower of amortized cost or fair value			214	[2]	748	[2]
Receivables held for sale at end of period	$ 1,840	$ 2,047	$ 1,840	[3]	$ 1,840	[3]

[1] During the first quarter of 2014, we identified a small pool of receivables held for sale which did not meet our criteria to be classified as held for sale. As a result we transferred these receivables to held for investment at the lower of amortized cost or fair value.

[2] The initial lower of amortized cost or fair value adjustment on receivables transferred into held for sale during the three and nine months ended September 30, 2014 totaled $10 million and $112 million, respectively.

[3] The following table provides a rollforward of our valuation allowance for the three and nine months ended September 30, 2014. The valuation allowance has been reduced to zero as the fair value of the pool of receivables held for sale at September 30, 2014 exceeds the carrying value as these receivables are carried at the lower of amortized cost or fair value. See Note 14, "Fair Value Measurements," for a discussion of the factors impacting the fair value of these receivables.