Finance Receivables and Loans, Net (Schedule of Sales of Financing Receivables and Loans) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, significant sales and transfers	$ 20	$ 1
Financing Receivable, Significant Sales	128
Loans held-for-sale transferred to finance receivables and loans held-for-investment	63	0
Consumer portfolio segment | Automobile loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, significant sales and transfers	20	0
Consumer portfolio segment | Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, significant sales and transfers	$ 0	$ 1