Receivables - TDR Loans (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015		Dec. 31, 2014
Financing Receivable, Modifications [Line Items]
Unpaid principal balance subject to reduction	$ 624		$ 549
TDR Loans held for investment, recorded at the lower of amortized cost or FV less cost to sell	399		517
Real Estate Secured [Member] | Receivables Held For Sale [Member]
Financing Receivable, Modifications [Line Items]
TDR Loans	831	[1],[2],[3]	650	[1],[2],[3]
Receivables Held For Sale [Member] | Real Estate Secured [Member]
Financing Receivable, Modifications [Line Items]
Unpaid balance of TDR loans	1,289		1,004
Real estate secured [Member]
Financing Receivable, Modifications [Line Items]
TDR Loans	11,032	[1],[2]	11,195	[1],[2]
Credit loss reserves for TDR loans	1,897	[3],[4]	1,982	[3],[4]
Unpaid balance of TDR loans	11,855		11,985
First Lien [Member]
Financing Receivable, Modifications [Line Items]
TDR Loans	9,315	[1],[2],[5]	9,630	[1],[2],[5]
Credit loss reserves for TDR loans	1,679	[4]	1,738	[4]
Unpaid balance of TDR loans	9,552		9,931
Second Lien [Member]
Financing Receivable, Modifications [Line Items]
TDR Loans	886	[1],[2],[5]	915	[1],[2],[5]
Credit loss reserves for TDR loans	218	[4]	244	[4]
Unpaid balance of TDR loans	$ 1,014		$ 1,050

[1] TDR Loans are considered to be impaired loans regardless of accrual status.

[2] The TDR Loan balances included in the table above reflect the current carrying amount of TDR Loans and includes all basis adjustments on the loan, such as unearned income, unamortized deferred fees and costs on originated loans and premiums or discounts on purchased loans as well as any charge-off recorded in accordance with our existing charge-off policies. Additionally, the carrying amount of TDR Loans classified as held for sale has been reduced by both the lower of amortized cost or fair value adjustment as well as the credit loss reserves associated with these receivables prior to the transfer. The following table reflects the unpaid principal balance of TDR Loans. Real Estate Secured: First lien $9,552 and $9,931 at March 31, 2015 and December 31, 2014, respectively; Second lien $1,014 and $1,050 at March 31, 2015 and December 31, 2014, respectively; Real estate secured receivables held for sale $1,289 and $1,004 at March 31, 2015 and December 31, 2014, respectively; Total real estate secured $11,855 and $11,985 at March 31, 2015 and December 31, 2014, respectively. At March 31, 2015 and December 31, 2014, the unpaid principal balances reflected above include $624 million and $549 million, respectively, which has received a reduction in the unpaid principal balance as part of an account management action.

[3] There are no credit loss reserves associated with receivables classified as held for sale as they are carried at the lower of amortized cost or fair value.

[4] Included in credit loss reserves.

[5] At March 31, 2015 and December 31, 2014, TDR Loans held for investment totaling $399 million and $517 million, respectively, are recorded at the lower of amortized cost or fair value of the collateral less cost to sell.