Receivables Held for Investment, net - Receivables Classified as Troubled Debt Restructuring Loan (Detail) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Receivables classified as Trouble Debt Restructuring Loans
TDR loans that became delinquent during the period		$ 85	$ 186	$ 453
Receivables Held For Sale [Member] | Real estate secured [Member]
Receivables classified as Trouble Debt Restructuring Loans
TDR loans that became delinquent during the period		70	90	33
First lien held for investment [Member]
Receivables classified as Trouble Debt Restructuring Loans
TDR loans that became delinquent during the period	[1]	7	72	367
Second lien held for investment [Member]
Receivables classified as Trouble Debt Restructuring Loans
TDR loans that became delinquent during the period	[1]	$ 8	$ 24	$ 53

[1] The amounts for 2016 reflect receivables held for investment which were classified as TDR Loans in the previous 12 months and became sixty days or greater contractually delinquent prior to the transfer of all receivables to receivables held for sale during the third quarter of 2016.