GM Financial Receivables and Transactions Retail Finance Receivables Delinquencies and TDRs (Details) - GM Financial [Member] $ in Millions	Mar. 31, 2019 USD ($) score	Dec. 31, 2018 USD ($) score
Delinquent Contracts [Abstract]
Finance receivables, individually evaluated for impairment, net of fees(b)	$ 2,367	$ 2,389
Allowance for loan losses - TDRs	$ 326	$ 325
Retail Finance Receivables [Member]
Financing Receivable, Recorded Investment, Additional Information [Abstract]
Percentage of receivables with sub-prime credit scores	24.00%	25.00%
Sub-prime FICO score \| score	620	620
Retail finance receivables, nonaccrual status	$ 745	$ 888
Delinquent Contracts [Abstract]
Past Due Amount	$ 1,507	$ 1,923
Percent of Contractual Amount Due	3.60%	5.60%
Finance receivables, individually evaluated for impairment, net of fees(b)	$ 2,333	$ 2,348
Allowance for loan losses - TDRs	324	321
31-to-60 days delinquent [Member] \| Retail Finance Receivables [Member]
Delinquent Contracts [Abstract]
Past Due Amount	$ 1,048	$ 1,265
Percent of Contractual Amount Due	2.50%	3.70%
Greater-than-60 days delinquent [Member] \| Retail Finance Receivables [Member]
Delinquent Contracts [Abstract]
Past Due Amount	$ 412	$ 605
Percent of Contractual Amount Due	1.00%	1.70%
Total finance receivables more than 30 days delinquent [Member] \| Retail Finance Receivables [Member]
Delinquent Contracts [Abstract]
Past Due Amount	$ 1,460	$ 1,870
Percent of Contractual Amount Due	3.50%	5.40%
In repossession [Member] \| Retail Finance Receivables [Member]
Delinquent Contracts [Abstract]
Past Due Amount	$ 47	$ 53
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.

+ References

No definition available.

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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.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
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- Definition

Percentage of financing receivable balance that is past due.

+ References

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
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- Definition

Recorded Investment in financing receivables that are past due at the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Paragraph 7A
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- References

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