GM Financial Receivables Retail Finance Receivables Delinquencies and TDRs (Details) - GM Financial [Member] - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Delinquent Contracts [Abstract]
Allowance for loan losses - TDRs	$ 292		$ 283
Retail Finance Receivables [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Retail finance receivables, nonaccrual status	711		807
Delinquent Contracts [Abstract]
Past Due Amount	$ 1,498	$ 1,432
Percent of Contractual Amount Due	4.20%	4.70%
Finance receivables classified as TDRs	$ 2,000		1,900
Allowance for loan losses - TDRs	284		$ 276
31-to-60 days delinquent [Member] \| Retail Finance Receivables [Member]
Delinquent Contracts [Abstract]
Past Due Amount	$ 1,006	$ 963
Percent of Contractual Amount Due	2.80%	3.10%
Greater-than-60 days delinquent [Member] \| Retail Finance Receivables [Member]
Delinquent Contracts [Abstract]
Past Due Amount	$ 441	$ 421
Percent of Contractual Amount Due	1.20%	1.40%
Total finance receivables more than 30 days delinquent [Member] \| Retail Finance Receivables [Member]
Delinquent Contracts [Abstract]
Past Due Amount	$ 1,447	$ 1,384
Percent of Contractual Amount Due	4.00%	4.50%
In repossession [Member] \| Retail Finance Receivables [Member]
Delinquent Contracts [Abstract]
Past Due Amount	$ 51	$ 48
Percent of Contractual Amount Due	0.20%	0.20%
North America [Member] \| Retail Finance Receivables [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Percentage of receivables with sub-prime credit scores	44.00%		48.00%
Sub-prime FICO score	620		620

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.

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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=66008989&loc=SL6953423-111524

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

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- Definition

Percent of financing receivables past due.

+ References

No definition available.

+ Details

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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
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=66008989&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
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: 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=66008989&loc=SL6953401-111524

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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.

+ References

No definition available.

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- References

No definition available.

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