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, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, significant sales and transfers	$ 940	$ 816	$ 960	$ 821
Financing Receivable, Sale			131
Loans held-for-sale transferred to finance receivables and loans held-for-investment			79
Consumer portfolio segment | Automotive loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, significant sales and transfers	0	578	20	578
Consumer portfolio segment | Real estate-backed loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, significant sales and transfers	940	0	940	5
Commercial portfolio segment | Commercial Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, significant sales and transfers	$ 0	$ 238	$ 0	$ 238