Finance Receivables and Loans, Net (Schedule of Average Balance and Interest Income of Impaired Finance Receivables) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Impaired [Line Items]
Average balance	$ 969	$ 889
Interest income	47	44
Consumer portfolio segment
Financing Receivable, Impaired [Line Items]
Average balance	730	707
Interest income	45	39
Commercial portfolio segment
Financing Receivable, Impaired [Line Items]
Average balance	239	182
Interest income	2	5
Automotive loan \| Consumer portfolio segment
Financing Receivable, Impaired [Line Items]
Average balance	510	478
Interest income	35	28
Automotive loan \| Commercial portfolio segment
Financing Receivable, Impaired [Line Items]
Average balance	113	93
Interest income	2	4
Real estate-backed loan \| Consumer portfolio segment
Financing Receivable, Impaired [Line Items]
Average balance	220	229
Interest income	10	11
Real estate-backed loan \| Commercial portfolio segment
Financing Receivable, Impaired [Line Items]
Average balance	5	5
Interest income	0	1
Mortgage Finance operations \| Consumer portfolio segment
Financing Receivable, Impaired [Line Items]
Average balance	14	11
Interest income	1	1
Mortgage - Legacy \| Consumer portfolio segment
Financing Receivable, Impaired [Line Items]
Average balance	206	218
Interest income	9	10
Other loan \| Commercial portfolio segment
Financing Receivable, Impaired [Line Items]
Average balance	121	84
Interest income	$ 0	$ 0

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

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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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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