Finance Receivables and Loans, Net (Schedule of Sales of Financing Receivables and Loans) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Significant Sales and Transfers	$ 31	$ 63	$ 1,335	$ 4,256
Consumer Portfolio Segment [Member] | Automobile Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Significant Sales and Transfers	28	57	1,326	4,216
Consumer Portfolio Segment [Member] | Residential Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Significant Sales and Transfers	3	6	9	12
Commercial Portfolio Segment [Member] | Commercial Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Significant Sales and Transfers	$ 0	$ 0	$ 0	$ 28