Finance Receivables - Troubled Debt Restructurings (Details) - Retail Finance Receivables [Member] $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020 USD ($) loan	Jun. 30, 2019 USD ($) loan	Jun. 30, 2018 USD ($) loan	Jun. 30, 2020 USD ($) loan	Jun. 30, 2019 USD ($) loan	Jun. 30, 2018 USD ($) loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans classified as TDRs during the period \| loan	14,378	17,407	19,662	29,646	33,939	33,096
Outstanding amortized cost of loans classified as TDRs during the period \| $	$ 248	$ 318	$ 360	$ 535	$ 626	$ 613

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

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- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

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