Finance Receivables and Loans, Net (Schedule of Average Balance and Interest Income of Impaired Finance Receivables) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2019
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	$ 918	$ 972
Impaired Financing Receivable, Interest Income, Accrual Method	11	34
Consumer portfolio segment
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	722	725
Impaired Financing Receivable, Interest Income, Accrual Method	11	33
Commercial portfolio segment
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	196	247
Impaired Financing Receivable, Interest Income, Accrual Method	0	1
Automotive loan \| Consumer portfolio segment
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	505	502
Impaired Financing Receivable, Interest Income, Accrual Method	9	26
Automotive loan \| Commercial portfolio segment
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	76	124
Impaired Financing Receivable, Interest Income, Accrual Method	0	1
Real estate-backed loan \| Consumer portfolio segment
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	217	223
Impaired Financing Receivable, Interest Income, Accrual Method	2	7
Real estate-backed loan \| Commercial portfolio segment
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	5	5
Impaired Financing Receivable, Interest Income, Accrual Method	0	0
Mortgage Finance operations \| Consumer portfolio segment
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	14	15
Impaired Financing Receivable, Interest Income, Accrual Method	0	0
Mortgage - Legacy \| Consumer portfolio segment
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	203	208
Impaired Financing Receivable, Interest Income, Accrual Method	2	7
Other loan \| Commercial portfolio segment
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	115	118
Impaired Financing Receivable, Interest Income, Accrual Method	$ 0	$ 0

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No definition available.

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- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5258-111524

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- Definition

Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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