Discontinued Operations - Financial Information for Assets and Liabilities of Businesses Held for Sale (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
ASSETS
Total assets held for sale	$ 0	$ 10,951
LIABILITIES
Total liabilities held for sale	$ 0	9,693
European Operations [Member] | Discontinued Operations [Member]
ASSETS
Cash and cash equivalents		386
Finance receivables, net		9,715
Related party receivables		163
Other assets		687
Total assets held for sale		10,951
LIABILITIES
Secured debt		4,183
Unsecured debt		5,130
Related party payables		80
Other liabilities		300
Total liabilities held for sale		$ 9,693