GM Financial Receivables and Transactions - Retail Finance Receivables Delinquencies (Details) - GM Financial $ in Millions	Dec. 31, 2019 USD ($) score	Dec. 31, 2018 USD ($) score	Dec. 31, 2017 USD ($)
Delinquent Contracts includes Repossessions [Abstract]
Finance receivables, individually evaluated for impairment, net of fees	$ 2,454	$ 2,389
Allowance for loan losses	$ 348	$ 325	$ 331
Retail Finance Receivables
Financing Receivable, Past Due [Line Items]
Percentage of Sub-prime Loans	24.00%	25.00%
Sub-prime FICO Score \| score	620	620
Retail finance receivables, nonaccrual status	$ 875	$ 888
Delinquent Contracts includes Repossessions [Abstract]
Amount	$ 1,940	$ 1,940
Percent of Contractual Amount Due	4.60%	4.80%
Finance receivables, individually evaluated for impairment, net of fees	$ 2,378	$ 2,348
Allowance for loan losses	330	321
31 to 60 Days Delinquent \| Retail Finance Receivables
Delinquent Contracts includes Repossessions [Abstract]
Amount	$ 1,354	$ 1,349
Percent of Contractual Amount Due	3.20%	3.30%
Greater than 60 Days Delinquent \| Retail Finance Receivables
Delinquent Contracts includes Repossessions [Abstract]
Amount	$ 542	$ 547
Percent of Contractual Amount Due	1.30%	1.40%
Total finance receivables more than 30 Days Delinquent \| Retail Finance Receivables
Delinquent Contracts includes Repossessions [Abstract]
Amount	$ 1,896	$ 1,896
Percent of Contractual Amount Due	4.50%	4.70%
In Repossession \| Retail Finance Receivables
Delinquent Contracts includes Repossessions [Abstract]
Amount	$ 44	$ 44
Percent of Contractual Amount Due	0.10%	0.10%

Sub-prime loans as percentage of the total loans.

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The FICO score used to separate sub-prime from prime loans. The loans with a borrower that has less then this score will be considered as sub-prime.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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Percentage of financing receivable balance that is past due.

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Amount of financing receivable on nonaccrual status.

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Amount of financing receivable past due.

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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.

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