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, 2019
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	$ 948	$ 990
Impaired Financing Receivable, Interest Income, Accrual Method	11	23
Consumer portfolio segment
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	721	724
Impaired Financing Receivable, Interest Income, Accrual Method	11	22
Commercial portfolio segment
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	227	266
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	498	498
Impaired Financing Receivable, Interest Income, Accrual Method	9	17
Automotive loan \| Commercial portfolio segment
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	113	143
Impaired Financing Receivable, Interest Income, Accrual Method	0	1
Other loan \| Commercial portfolio segment
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	108	117
Impaired Financing Receivable, Interest Income, Accrual Method	0	0
Real estate-backed loan \| Consumer portfolio segment
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	223	226
Impaired Financing Receivable, Interest Income, Accrual Method	2	5
Real estate-backed loan \| Commercial portfolio segment
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	6	6
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	209	211
Impaired Financing Receivable, Interest Income, Accrual Method	$ 2	$ 5

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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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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