Equity in Net Assets of Non-consolidated Affiliates (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Noncontrolling Interest [Line Items]
Net income	$ 45	$ 52
Joint Ventures [Member]
Noncontrolling Interest [Line Items]
Finance charge income	350	307
Provision for loan losses	6	3
Interest expense	152	124
Income before income taxes	170	198
Net income	127	$ 148
Undistributed earnings	$ 543		$ 498

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Equity Method Investment, Summarized Financial Information, Provision for Loan Losses

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