GM Financial Receivables and Transactions - Retail Finance Receivables Delinquencies (Details) - Retail Finance Receivables - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Past Due [Line Items]
TDR's	$ 2,200
Nonaccrual loans	301
GM Financial
Financing Receivable, Past Due [Line Items]
Retail finance receivables, nonaccrual status	714	$ 875
2020	26,183
2019	12,050
2018	7,463
2017	3,693
2016	1,390
Prior	$ 509
Total		$ 1,940
Percent	100.00%	100.00%
Percent		4.60%
Percent	100.00%
GM Financial \| Nonperforming Financial Instruments
Financing Receivable, Past Due [Line Items]
2020	$ 289
2019	459
2018	332
2017	239
2016	141
Prior	88
Total	$ 1,548
Percent	3.00%
0-to-30 days \| GM Financial \| Performing Financial Instruments
Financing Receivable, Past Due [Line Items]
2020	$ 25,894
2019	11,591
2018	7,131
2017	3,454
2016	1,249
Prior	421
Total, Not Past Due	$ 49,740
Percent	97.00%
31-to-60 days \| GM Financial
Financing Receivable, Past Due [Line Items]
Total		$ 1,354
Percent		3.20%
31-to-60 days \| GM Financial \| Nonperforming Financial Instruments
Financing Receivable, Past Due [Line Items]
2020	$ 210
2019	325
2018	235
2017	170
2016	102
Prior	61
Total	$ 1,103
Percent	2.10%
Greater-than-60 days \| GM Financial
Financing Receivable, Past Due [Line Items]
Total		$ 542
Percent		1.30%
Greater-than-60 days \| GM Financial \| Nonperforming Financial Instruments
Financing Receivable, Past Due [Line Items]
2020	$ 72
2019	123
2018	90
2017	64
2016	37
Prior	26
Total	$ 412
Percent	0.80%
Finance receivables more than 30 days delinquent \| GM Financial
Financing Receivable, Past Due [Line Items]
Total		$ 1,896
Percent		4.50%
Finance receivables more than 30 days delinquent \| GM Financial \| Nonperforming Financial Instruments
Financing Receivable, Past Due [Line Items]
2020	$ 282
2019	448
2018	325
2017	234
2016	139
Prior	87
Total	$ 1,515
Percent	2.90%
In repossession \| GM Financial
Financing Receivable, Past Due [Line Items]
Total		$ 44
Percent		0.10%
In repossession \| GM Financial \| Nonperforming Financial Instruments
Financing Receivable, Past Due [Line Items]
2020	$ 7
2019	11
2018	7
2017	5
2016	2
Prior	1
Total	$ 33
Percent	0.10%

Financing Receivable, before Allowance for Credit Loss, Percent

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Financing Receivable, including Past Due, Percent

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Impaired Financing Receivable, Nonaccrual

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Amount of financing receivable originated more than five years prior to current fiscal year.

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Amount of financing receivable originated in current fiscal year.

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Percentage of financing receivable balance that is past due.

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