Receivables Held for Sale - Summary of Activity in Receivables Held for Sale (Detail) - USD ($) $ in Millions		1 Months Ended	12 Months Ended
		Sep. 30, 2016	Dec. 31, 2016		Dec. 31, 2015		Dec. 31, 2014
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]		5,674		$ 8,265
Receivables Held for Sale, Initial Lower of Amortized Cost or Fair Value Adjustment		$ (541)	(587)		(234)
Mortgage Loans on Real Estate [Member]
Receivables Held for Sale, Activity [Roll Forward]
Real estate secured receivables held for sale at beginning of period			8,265	[3]	860	[3]	$ 2,047
Transfer of real estate secured receivables into held for sale at the lower of amortized cost or fair value	[4],[5]		7,574		10,327		909
Real estate secured receivable sales			(8,973)		(1,995)		(2,152)
Lower of amortized cost or fair value adjustment on receivables held for sale			(201)		(130)		314
Carrying value of real estate secured receivables held for sale transferred to REO			(54)		(93)		(182)
Carrying value of real estate secured receivables held for sale settled through short sale			(33)		(55)		(61)
Change in real estate secured receivable balance, including collections			(904)		(649)		30
Transfer of real estate secured receivables into held for investment at the lower of amortized cost or fair value	[6]		0		0		(45)
Real estate secured receivables held for sale at end of period	[3]		5,674		8,265		860
Other Revenue [Member]
Receivables Held for Sale, Activity [Roll Forward]
Receivables Held for Sale, Initial Lower of Amortized Cost or Fair Value Adjustment	[7]		$ (11)		$ 0		$ (113)

[1] At December 31, 2016, receivables held for sale includes $750 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 17, "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] Real estate secured receivables held for sale in the table above are presented net of the valuation allowance.

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

[5] The initial lower of amortized cost or fair value adjustment on receivables transferred into held for sale during the years ended December 31, 2016, 2015 and 2014 totaled $587 million, $234 million and $113 million, respectively.

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

[7] Represents the portion of the initial lower of amortized cost or fair value adjustment attributable to non-credit factors which are recorded as a component of total other revenues in the consolidated statement income (loss) as it reflects the impact on value caused by current marketplace conditions including changes in interest rates.