Equity in Net Assets of Non-consolidated Affiliates (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Noncontrolling Interest [Line Items]
Net income	$ 42	$ 45	$ 87	$ 97
Joint Ventures [Member]
Noncontrolling Interest [Line Items]
Finance charge income	344	315	694	622
Income before income taxes	161	171	331	369
Net income	121	$ 129	248	$ 277
Undistributed earnings	$ 585		$ 585		$ 498

Amount of income (loss) from continuing operations reported by an equity method investee.

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