Equity in Net Assets of Non-consolidated Affiliates (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Noncontrolling Interest [Line Items]
Finance charge income	$ 966	$ 1,008	$ 1,972	$ 1,995
Income before income taxes	226	536	456	895
Net income	42	42	67	87
Joint Ventures [Member]
Noncontrolling Interest [Line Items]
Finance charge income	335	344	694	694
Income before income taxes	158	161	254	331
Net income	118	$ 121	190	$ 248
Undistributed earnings	$ 666		$ 666		$ 615