GM Financial Receivables and Transactions - Retail Finance Receivables Delinquencies and TDRs (Details) - GM Financial [Member] $ in Millions	Jun. 30, 2019 USD ($) score	Dec. 31, 2018 USD ($) score
Delinquent Contracts [Abstract]
Finance receivables, individually evaluated for impairment, net of fees	$ 2,403	$ 2,389
Allowance for loan losses - TDRs	$ 352	$ 325
Retail Finance Receivables [Member]
Financing Receivable, Recorded Investment, Additional Information [Abstract]
Percentage of receivables with sub-prime credit scores	23.00%	25.00%
Sub-prime FICO score \| score	620	620
Retail finance receivables, nonaccrual status	$ 838	$ 888
Delinquent Contracts [Abstract]
Past Due Amount	$ 1,629	$ 1,697
Percent of Contractual Amount Due	3.80%	4.80%
Finance receivables, individually evaluated for impairment, net of fees	$ 2,354	$ 2,348
Allowance for loan losses - TDRs	341	321
31-to-60 days delinquent [Member] \| Retail Finance Receivables [Member]
Delinquent Contracts [Abstract]
Past Due Amount	$ 1,083	$ 1,178
Percent of Contractual Amount Due	2.50%	3.30%
Greater-than-60 days delinquent [Member] \| Retail Finance Receivables [Member]
Delinquent Contracts [Abstract]
Past Due Amount	$ 498	$ 462
Percent of Contractual Amount Due	1.20%	1.30%
Total finance receivables more than 30 days delinquent [Member] \| Retail Finance Receivables [Member]
Delinquent Contracts [Abstract]
Past Due Amount	$ 1,581	$ 1,640
Percent of Contractual Amount Due	3.70%	4.60%
In repossession [Member] \| Retail Finance Receivables [Member]
Delinquent Contracts [Abstract]
Past Due Amount	$ 48	$ 57
Percent of Contractual Amount Due	0.10%	0.20%

Financing Receivable, Recorded Investment, Additional Information [Abstract]

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- Definition

Sub-prime loans as percentage of the total loans.

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- Definition

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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- Definition

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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