Finance Receivables and Loans, Net (Schedule of Average Balance and Interest Income of Impaired Finance Receivables) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Financing Receivable, Impaired [Line Items]
Financing receivable, impaired, average balance	$ 948	$ 865	$ 990	$ 822
Financing receivable, impaired, interest income	11	11	23	21
Consumer portfolio segment
Financing Receivable, Impaired [Line Items]
Financing receivable, impaired, average balance	721	700	724	691
Financing receivable, impaired, interest income	11	10	22	19
Consumer portfolio segment \| Automotive loan
Financing Receivable, Impaired [Line Items]
Financing receivable, impaired, average balance	498	472	498	462
Financing receivable, impaired, interest income	9	7	17	14
Consumer portfolio segment \| Real estate-backed loan
Financing Receivable, Impaired [Line Items]
Financing receivable, impaired, average balance	223	228	226	229
Financing receivable, impaired, interest income	2	3	5	5
Consumer portfolio segment \| Mortgage Finance operations
Financing Receivable, Impaired [Line Items]
Financing receivable, impaired, average balance	14	9	15	9
Financing receivable, impaired, interest income	0	0	0	0
Consumer portfolio segment \| Mortgage - Legacy
Financing Receivable, Impaired [Line Items]
Financing receivable, impaired, average balance	209	219	211	220
Financing receivable, impaired, interest income	2	3	5	5
Commercial portfolio segment
Financing Receivable, Impaired [Line Items]
Financing receivable, impaired, average balance	227	165	266	131
Financing receivable, impaired, interest income	0	1	1	2
Commercial portfolio segment \| Automotive loan
Financing Receivable, Impaired [Line Items]
Financing receivable, impaired, average balance	113	78	143	61
Financing receivable, impaired, interest income	0	1	1	2
Commercial portfolio segment \| Real estate-backed loan
Financing Receivable, Impaired [Line Items]
Financing receivable, impaired, average balance	6	5	6	4
Financing receivable, impaired, interest income	0	0	0	0
Commercial portfolio segment \| Other loan
Financing Receivable, Impaired [Line Items]
Financing receivable, impaired, average balance	108	82	117	66
Financing receivable, impaired, interest income	$ 0	$ 0	$ 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=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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- 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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