Finance Receivables and Loans, Net (Finance Receivables and Loans Redefaulted During the Period) (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022 USD ($) loan	Sep. 30, 2021 USD ($) loan	Sep. 30, 2022 USD ($) loan	Sep. 30, 2021 USD ($) loan	Dec. 31, 2021 USD ($)
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	2,621	2,374	6,952	6,944
Amortized cost	$ 39	$ 31	$ 107	$ 86
Charge-off amount	47	$ 15	74	$ 46
Total finance receivables and loans	$ 132,456		$ 132,456		$ 122,268
Consumer
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	2,620	2,374	6,951	6,944
Amortized cost	$ 38	$ 31	$ 106	$ 86
Charge-off amount	16	$ 15	43	$ 46
Total finance receivables and loans	$ 106,720		$ 106,720		98,226
Consumer \| Consumer automotive
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	2,473	2,374	6,722	6,939
Amortized cost	$ 37	$ 31	$ 103	$ 86
Charge-off amount	16	$ 15	43	$ 46
Total finance receivables and loans	$ 83,459		$ 83,459		78,252
Consumer \| Consumer mortgage
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	1	0	4	5
Amortized cost	$ 1	$ 0	$ 3	$ 0
Charge-off amount	0	$ 0	0	$ 0
Total finance receivables and loans	$ 20,021		$ 20,021		18,012
Consumer \| Mortgage Finance
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	1	0	4	1
Amortized cost	$ 1	$ 0	$ 3	$ 0
Charge-off amount	0	$ 0	0	$ 0
Total finance receivables and loans	19,715		$ 19,715		17,644
Consumer \| Mortgage - Legacy
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan			0	4
Amortized cost			$ 0	$ 0
Charge-off amount			0	$ 0
Total finance receivables and loans	$ 306		$ 306		368
Consumer \| Other
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	146	0	225	0
Amortized cost	$ 0	$ 0	$ 0	$ 0
Charge-off amount	0	$ 0	0	$ 0
Total finance receivables and loans	$ 3,240		$ 3,240		1,962
Consumer \| Credit card receivables
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	146	0	225	0
Amortized cost	$ 0	$ 0	$ 0	$ 0
Charge-off amount	0	$ 0	0	$ 0
Total finance receivables and loans	$ 1,427		$ 1,427		953
Commercial
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	1	0	1	0
Amortized cost	$ 1	$ 0	$ 1	$ 0
Charge-off amount	31	$ 0	31	$ 0
Total finance receivables and loans	25,736		25,736		24,042
Commercial \| Consumer automotive
Accounts, Notes, Loans and Financing Receivable
Total finance receivables and loans	12,158		12,158		12,229
Commercial \| Consumer mortgage
Accounts, Notes, Loans and Financing Receivable
Total finance receivables and loans	$ 5,153		$ 5,153		4,939
Commercial \| Other
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	1	0	1	0
Amortized cost	$ 1	$ 0	$ 1	$ 0
Charge-off amount	31	$ 0	31	$ 0
Total finance receivables and loans	$ 8,425		$ 8,425		$ 6,874

Financing Receivables, Troubled Debt Restructuring, Write-down

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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919230-210447

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 3B
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL120267963-210447

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+ References

No definition available.

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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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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)
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