Receivables, net - Nonperforming Consumer Receivable Portfolio (Detail) - USD ($) $ in Millions		Dec. 31, 2015		Dec. 31, 2014		Dec. 31, 2013	[4]	Dec. 31, 2012
Financing Receivable, Impaired [Line Items]
Real estate secured	[1],[2],[3]	$ 9,156		$ 22,670
Receivables held for sale		8,265	[3],[4]	860	[3],[4]	$ 2,047		$ 6,203
Total	[3]	17,421		23,530
Nonaccrual loans carried at lower of amortized cost of fair value less cost to sell but less than 90 days delinquent		501		627
Accruing Loans [Member]
Financing Receivable, Impaired [Line Items]
Real estate secured	[1],[2],[3]	8,873		21,646
Receivables held for sale	[3]	7,879		351
Total	[3]	16,752		21,997
Nonaccrual Loans [Member]
Financing Receivable, Impaired [Line Items]
Real estate secured	[1],[2],[3],[5]	283		1,024
Receivables held for sale	[3],[5]	386		509
Total	[3],[5]	669		1,533
Nonperforming receivables held for investment (TDR)		178		739
Nonaccrual Loans [Member] | Real Estate Secured [Member]
Financing Receivable, Impaired [Line Items]
Nonperforming receivables held for investment		$ 187		$ 417

[1] At December 31, 2015 and December 31, 2014, nonperforming real estate secured receivables held for investment include $178 million and $739 million, respectively, of TDR Loans, some of which may also be carried at fair value of the collateral less cost to sell

[2] At December 31, 2015 and December 31, 2014, nonperforming real estate secured receivables held for investment include $187 million and $417 million, respectively, of receivables that are carried at the lower of amortized cost or fair value of the collateral less cost to sell.

[3] The 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 loans. 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.

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

[5] Nonperforming receivables do not include receivables totaling $501 million and $627 million at December 31, 2015 and December 31, 2014, respectively, which are less than 90 days contractually delinquent and not accruing interest.