Receivables - Receivables and Receivables held for Sale (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	[1]	$ 106	$ 217	$ 257	$ 489
First lien [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total		17	169	142	394
Second lien [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total		12	23	28	51
Real Estate Secured Receivables Held for Sale [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total		$ 77	$ 25	$ 87	$ 44

[1] The following table summarizes the actions taken during the three and six months ended June 30, 2015, and 2014 which resulted in the above receivables being classified as a TDR loan. Modifications, primarily interest rate modifications, of $40 million and $80 million for the three months ended June 30, 2015 and 2014, respectively. Modifications, primarily interest rate modifications, of $100 million and $164 million for the six months ended June 30, 2015 and 2014, respectively; Re-age of past due accounts of $66 million and $137 million for the three months ended June 30, 2015 and 2014, respectively; Re-age of past due accounts of Total of $157 million and $325 million for the six months ended June 30, 2015 and 2014, respectively. During the first quarter of 2015, it was determined that loan balances totaling $160 million previously reported as modifications in the table above during the first quarter of 2014 should have been reported as a re-age. Accordingly, the modification and re-age information presented in the table above for the six months ended June 30, 2014 has been adjusted to reflect the corrected classification. The total amounts reported remain unchanged.