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, 2018	Sep. 30, 2019	Sep. 30, 2018
Financing Receivable, Impaired [Line Items]
Financing receivable, impaired, average balance	$ 918	$ 905	$ 972	$ 852
Financing receivable, impaired, interest income	11	10	34	31
Consumer portfolio segment
Financing Receivable, Impaired [Line Items]
Financing receivable, impaired, average balance	722	714	725	706
Financing receivable, impaired, interest income	11	10	33	29
Consumer portfolio segment \| Automotive loan
Financing Receivable, Impaired [Line Items]
Financing receivable, impaired, average balance	505	485	502	477
Financing receivable, impaired, interest income	9	7	26	21
Consumer portfolio segment \| Real estate-backed loan
Financing Receivable, Impaired [Line Items]
Financing receivable, impaired, average balance	217	229	223	229
Financing receivable, impaired, interest income	2	3	7	8
Consumer portfolio segment \| Mortgage Finance operations
Financing Receivable, Impaired [Line Items]
Financing receivable, impaired, average balance	14	12	15	10
Financing receivable, impaired, interest income	0	1	0	1
Consumer portfolio segment \| Mortgage - Legacy
Financing Receivable, Impaired [Line Items]
Financing receivable, impaired, average balance	203	217	208	219
Financing receivable, impaired, interest income	2	2	7	7
Commercial portfolio segment
Financing Receivable, Impaired [Line Items]
Financing receivable, impaired, average balance	196	191	247	146
Financing receivable, impaired, interest income	0	0	1	2
Commercial portfolio segment \| Automotive loan
Financing Receivable, Impaired [Line Items]
Financing receivable, impaired, average balance	76	83	124	65
Financing receivable, impaired, interest income	0	0	1	2
Commercial portfolio segment \| Real estate-backed loan
Financing Receivable, Impaired [Line Items]
Financing receivable, impaired, average balance	5	7	5	5
Financing receivable, impaired, interest income	0	0	0	0
Commercial portfolio segment \| Other loan
Financing Receivable, Impaired [Line Items]
Financing receivable, impaired, average balance	115	101	118	76
Financing receivable, impaired, interest income	$ 0	$ 0	$ 0	$ 0

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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=118936363&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=118936363&loc=d3e5258-111524

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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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