GM Financial Receivables Retail Finance Receivables Delinquencies (Details) - GM Financial [Member] $ in Millions	Dec. 31, 2017 USD ($) score	Dec. 31, 2016 USD ($) score	Dec. 31, 2015 USD ($)
Delinquent Contracts includes Repossessions [Abstract]
Finance receivables, individually evaluated for impairment, net of fees	$ 2,250	$ 1,947
Allowance for loan losses - TDRs	$ 331	$ 280	$ 225
Retail Finance Receivables [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Percentage of Sub-prime Loans	33.00%	41.00%
Sub-prime FICO Score \| score	620	620
Retail finance receivables, nonaccrual status	$ 778	$ 798
Delinquent Contracts includes Repossessions [Abstract]
Amount	$ 1,920	$ 1,799
Percent of Contractual Amount Due	5.80%	6.80%
Finance receivables, individually evaluated for impairment, net of fees	$ 2,228	$ 1,920
Allowance for loan losses - TDRs	328	276
31 to 60 Days Delinquent [Member] \| Retail Finance Receivables [Member]
Delinquent Contracts includes Repossessions [Abstract]
Amount	$ 1,334	$ 1,220
Percent of Contractual Amount Due	4.10%	4.60%
Greater than 60 Days Delinquent [Member] \| Retail Finance Receivables [Member]
Delinquent Contracts includes Repossessions [Abstract]
Amount	$ 559	$ 532
Percent of Contractual Amount Due	1.70%	2.00%
Total finance receivables more than 30 Days Delinquent [Member] \| Retail Finance Receivables [Member]
Delinquent Contracts includes Repossessions [Abstract]
Amount	$ 1,893	$ 1,752
Percent of Contractual Amount Due	5.80%	6.60%
In Repossession [Member] \| Retail Finance Receivables [Member]
Delinquent Contracts includes Repossessions [Abstract]
Amount	$ 27	$ 47
Percent of Contractual Amount Due	0.00%	0.20%

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.

+ References

No definition available.

+ Details

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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://www.xbrl.org/2003/role/presentationRef
-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

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

Percentage of financing receivable balance that is past due.

+ References

No definition available.

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953401-111524

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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

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- References

No definition available.

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