GM Financial Receivables and Transactions - Commercial Finance Receivables Credit Quality Indicators (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
GM Financial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
GM Financial receivables, net of fees	$ 56,756	$ 53,900
Commercial Finance Receivables [Member] \| GM Financial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Revolving	7,110
2020	356
2019	193
2018	105
2017	103
2016	117
2015	56
Prior	22
GM Financial receivables, net of fees	$ 8,062	$ 11,671
Percent	100.00%
Commercial Finance Receivables [Member] \| GM Financial [Member] \| Group I - Performing accounts with strong to acceptable financial metrics [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Revolving	$ 6,468
2020	355
2019	177
2018	73
2017	98
2016	93
2015	38
Prior	0
GM Financial receivables, net of fees	$ 7,302
Percent	90.60%
Commercial Finance Receivables [Member] \| GM Financial [Member] \| Group II - Performing accounts experiencing potential weakness in financial metrics [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Revolving	$ 411
2020	1
2019	7
2018	3
2017	3
2016	13
2015	13
Prior	22
GM Financial receivables, net of fees	$ 473
Percent	5.90%
Commercial Finance Receivables [Member] \| GM Financial [Member] \| Group III - Non-Performing accounts with inadequate paying capacity for current obligations [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Revolving	$ 227
2020	0
2019	9
2018	29
2017	2
2016	11
2015	1
Prior	0
GM Financial receivables, net of fees	$ 279
Percent	3.40%
Commercial Finance Receivables [Member] \| GM Financial [Member] \| Group IV - Non-Performing accounts with inadequate paying capacity for current obligations and inherent weaknesses [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Revolving	$ 4
2020	0
2019	0
2018	0
2017	0
2016	0
2015	4
Prior	0
GM Financial receivables, net of fees	$ 8
Percent	0.10%
Floorplan Advances [Member] \| Commercial Finance Receivables [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Percent of revolving balance	98.00%

Financing Receivable, Originated Five Years before Latest Fiscal Year

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- Definition

Financing Receivable, Originated, More than Six Years before Current Fiscal Year

+ References

No definition available.

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- Definition

Financing Receivable, Revolving, Percent of Total

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- Definition

Financing Receivable, before Allowance for Credit Loss, Percent

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- Definition

Amount of financing receivable originated four years prior to current fiscal year.

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- Definition

Amount of financing receivable originated in current fiscal year.

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- Definition

Amount of financing receivable originated in fiscal year prior to current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
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- Definition

Amount of financing receivable originated three years prior to current fiscal year.

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- Definition

Amount of financing receivable originated two years prior to current fiscal year.

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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

Amount of financing receivable that can be withdrawn, repaid and redrawn.

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- Definition

Amount, before allowance for credit loss, of financing receivable.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 55
-Paragraph 79
-URI http://asc.fasb.org/extlink&oid=121647567&loc=SL82922352-210448

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-URI http://asc.fasb.org/extlink&oid=121647567&loc=SL82922355-210448

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