Finance Receivables and Loans, Net (Finance Receivables and Loans Redefaulted During the Period) (Details) - Consumer $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022 USD ($) loan	Jun. 30, 2021 USD ($) loan	Jun. 30, 2022 USD ($) loan	Jun. 30, 2021 USD ($) loan
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	2,218	1,754	4,331	4,570
Amortized cost	$ 35	$ 22	$ 68	$ 55
Charge-off amount	$ 14	$ 11	$ 27	$ 31
Automotive loan
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	2,138	1,751	4,249	4,565
Amortized cost	$ 35	$ 22	$ 66	$ 55
Charge-off amount	$ 14	$ 11	$ 27	$ 31
Mortgage/Real Estate
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	1	3	3	5
Amortized cost	$ 0	$ 0	$ 2	$ 0
Charge-off amount	$ 0	$ 0	$ 0	$ 0
Mortgage Finance
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	1	1	3	1
Amortized cost	$ 0	$ 0	$ 2	$ 0
Charge-off amount	$ 0	$ 0	$ 0	$ 0
Mortgage - Legacy
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	0	2	0	4
Amortized cost	$ 0	$ 0	$ 0	$ 0
Charge-off amount	$ 0	$ 0	$ 0	$ 0
Other
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	79	0	79	0
Amortized cost	$ 0	$ 0	$ 0	$ 0
Charge-off amount	$ 0	$ 0	$ 0	$ 0
Credit card receivables
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	79	0	79	0
Amortized cost	$ 0	$ 0	$ 0	$ 0
Charge-off amount	$ 0	$ 0	$ 0	$ 0

Financing Receivables, Troubled Debt Restructuring, Write-down

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- Definition

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.

+ References

No definition available.

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- Definition

Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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- Definition

Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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