Receivables Held For Sale - Allowance for Credit Losses Rollforward (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	$ 3	$ 150	$ 174	$ 13
Initial valuation allowance for real estate secured receivables transferred to held for sale during the period	0	5	0	11
Increase (decrease) in valuation allowance resulting from changes in fair value	10	15	(153)	145
Change in valuation allowance for receivables sold	(5)	(81)	(5)	(81)
Change in valuation allowance for collections, charged-off, transferred to REO or short sale	(1)	(1)	(9)	0
Balance at end of period	$ 7	$ 88	$ 7	$ 88

Allowance for Loan and Lease Losses Held-for-Sale, Fair Value Adjustments

No definition available.

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Allowance for Loan and Lease Losses Held-for-Sale, Transfer Made to Held-for-Sale Loans, Adjustment

No definition available.

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Allowance for Loans and Lease Losses Held-for-Sale, Period Increase (Decrease) to Valuation Allowance for Loans Sold

No definition available.

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Allowance for Loans and Lease Losses Held-for-Sale, Recovery of Bad Debts, Write-offs, Transfers

No definition available.

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Loans and Leases Receivable Held for Sale Valuation Allowance

No definition available.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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