Receivables Held for Sale - Summary of Activity in Receivables Held for Sale (Detail) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Receivables Held for Sale, Activity [Roll Forward]
Real estate secured receivables held for sale at beginning of period	[1],[2]			$ 8,265
Real estate secured receivables held for sale at end of period	[1],[2]	$ 10,148		10,148
Mortgage Loans on Real Estate [Member]
Receivables Held for Sale, Activity [Roll Forward]
Real estate secured receivables held for sale at beginning of period		3,796	$ 10,310	8,265	$ 860
Transfer of real estate secured receivables into held for sale at the lower of amortized cost or fair value	[3],[4]	7,281	248	7,574	10,250
Real estate secured receivable sales		(714)	(107)	(4,933)	(408)
Lower of amortized cost or fair value adjustment on receivables held for sale		(3)	(83)	(108)	(154)
Carrying value of real estate secured receivables held for sale transferred to REO		(11)	(25)	(45)	(71)
Carrying value of real estate secured receivables held for sale settled through short sale		(8)	(15)	(26)	(41)
Change in real estate secured receivable balance, including collections		(193)	(287)	(579)	(395)
Real estate secured receivables held for sale at end of period	[5]	$ 10,148	$ 10,041	$ 10,148	$ 10,041

[1] At September 30, 2016, receivables held for sale includes $790 million of closed-end real estate secured receivables which are part of a collateralized funding transaction. These receivables will be sold when they are contractually released as collateral under the public trust and become available for sale. See Note 11, “Variable Interest Entities,” for further discussion of our collateralized funding transactions.

[2] The receivable balances included in this table reflect the principal amount outstanding on the loan net of any charge-off recorded in accordance with our existing charge-off policies but exclude any basis adjustments to the loan such as unearned income, unamortized deferred fees and costs on originated loans, purchase accounting fair value adjustments and premiums or discounts on purchased receivables. Additionally, the balances in this table related to receivables which have been classified as held for sale have been reduced by the lower of amortized cost or fair value adjustment recorded as well as the credit loss reserves associated with these receivables prior to the transfer.

[3] Amount includes any accrued interest associated with the receivable.

[4] 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, 2016 totaled $562 million and $587 million, respectively. During the three and nine months ended September 30, 2015, the initial lower of amortized cost or fair value adjustment on receivables transferred to held for sale was $12 million and $232 million, respectively.

[5] Real estate secured receivables held for sale in the table above are presented net of the valuation allowance.