Finance Receivables and Loans, Net (Schedule of Sales of Financing Receivables and Loans) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Sale	$ 960	$ 826
Financing receivable, sales and transfers	131
Loans held-for-sale transferred to finance receivables and loans held-for-investment	79
Consumer portfolio segment \| Automotive loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Sale	20	578
Consumer portfolio segment \| Real estate-backed loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Sale	940	10
Commercial portfolio segment \| Commercial Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Sale	$ 0	$ 238

Financing Receivable, sale initially classified as held-for-investment

No definition available.

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- Definition

Loans held-for-sale transferred to finance receivables and loans held-for-investment

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Amount of decrease from sale and reclassification to held-for-sale of financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 11
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919244-210447

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

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