Minimum liquidity which must be maintained pursuant to debt covenants under the line of credit arrangement.

No definition available.

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Period Type:	duration

- Definition

New debt issued during the period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The increase in the maximum borrowing capacity of the facility during the period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Number of agency ratings needed to maintain an investment grade credit rating and avoid additional guarantee requirements as part of the revolving credit facility agreements.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

The maximum borrowing capacity available to support issuances of letters of credit under the revolving credit agreement.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

The maximum borrowing capacity available to a specified subsidiary under the revolving credit agreement.

+ References

No definition available.

+ Details

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- Definition

The number of credit facilities entered into.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Overnight deposits expressed as a percentage of total deposits.

+ References

No definition available.

+ Details

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Namespace Prefix:	gm_
Data Type:	num:percentItemType
Balance Type:	na
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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

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-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Balance Type:	na
Period Type:	instant

- 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

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of foreign interest-bearing deposits held by the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 235
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-05(a))
-URI http://asc.fasb.org/extlink&oid=6882215&loc=d3e537907-122884

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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Details

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Automotive and GM Financial Debt Other Disclosures (Details) € in Millions, $ in Millions	1 Months Ended	6 Months Ended	7 Months Ended
	May 31, 2016 USD ($)	Jun. 30, 2016 USD ($)	Jul. 31, 2016 USD ($)	May 31, 2016 EUR (€)	Apr. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Feb. 29, 2016 USD ($)
Automotive [Member] \| Unsecured Debt [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Number of Credit Facilities	2
Automotive [Member] \| Unsecured Debt [Member] \| Revolving Credit Facility October 2014 [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity					$ 12,500
Automotive [Member] \| Unsecured Debt [Member] \| Revolving Credit Facility May 2016 [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 14,500
Debt Covenant Minimum Liquidity Requirement	4,000
Automotive [Member] \| Unsecured Debt [Member] \| Revolving Credit Facility May 2016 [Member] \| U.S.
Debt Instrument [Line Items]
Debt Covenant Minimum Liquidity Requirement	$ 2,000
Automotive [Member] \| Unsecured Debt [Member] \| Revolving Credit Facility May 2016 [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Number of agencies needed to maintain investment grade rating	2			2
Automotive [Member] \| Unsecured Debt [Member] \| Three-year Revolving Credit Facility May 2016 [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 4,000
Debt Instrument, Term	3 years
Sublimit Available for Issuance of Letters of Credit	$ 1,000
Automotive [Member] \| Unsecured Debt [Member] \| Five-year Revolving Credit Facility May 2016 [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 10,500
Debt Instrument, Term	5 years
Sublimit Available for Issuance of Letters of Credit	$ 500
Automotive [Member] \| Unsecured Debt [Member] \| Senior Notes Issued February 2016 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount							$ 2,000
Automotive [Member] \| Unsecured Debt [Member] \| Senior Notes 2036 at 6.60% [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount							$ 1,250
Debt Instrument, Interest Rate, Stated Percentage							6.60%
Debt Instrument, Maturity Date		Dec. 31, 2036
Automotive [Member] \| Unsecured Debt [Member] \| Senior Notes 2046 at 6.75% [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount							$ 750
Debt Instrument, Interest Rate, Stated Percentage							6.75%
Debt Instrument, Maturity Date		Dec. 31, 2046
Automotive [Member] \| Unsecured Debt [Member] \| GM Financial Segment [Member] \| Three-year Revolving Credit Facility May 2016 [Member]
Debt Instrument [Line Items]
Sublimit Available to GM Financial	1,000
Automotive [Member] \| Unsecured Debt [Member] \| GM Financial Segment [Member] \| Five-year Revolving Credit Facility May 2016 [Member]
Debt Instrument [Line Items]
Sublimit Available to GM Financial	3,000
GM Financial [Member] \| Secured Debt [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line Of Credit Increase Maximum Borrowing Capacity		$ 2,500
GM Financial [Member] \| Secured Debt [Member] \| Securitization notes payable [Member]
Debt Instrument [Line Items]
Securitization Notes Payable Issued		8,400
GM Financial [Member] \| Unsecured Debt [Member] \| GERMANY
Debt Instrument [Line Items]
Deposits		$ 1,800
Overnight Deposits, Percentage of Total Deposits		36.00%
GM Financial [Member] \| Unsecured Debt [Member] \| Senior Notes Issued March 2016 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount						$ 2,750
GM Financial [Member] \| Unsecured Debt [Member] \| Senior Notes March 2021 at 4.2% [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount						$ 1,500
Debt Instrument, Interest Rate, Stated Percentage						4.20%
Debt Instrument, Maturity Date		Mar. 31, 2021
GM Financial [Member] \| Unsecured Debt [Member] \| Senior Notes March 2026 at 5.25% [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount						$ 1,250
Debt Instrument, Interest Rate, Stated Percentage						5.25%
Debt Instrument, Maturity Date		Mar. 31, 2026
GM Financial [Member] \| Unsecured Debt [Member] \| Senior Notes Issued May 2016 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	3,000
GM Financial [Member] \| Unsecured Debt [Member] \| Senior Notes May 2019 at 2.40% [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 1,400
Debt Instrument, Interest Rate, Stated Percentage	2.40%			2.40%
Debt Instrument, Maturity Date		May 31, 2019
GM Financial [Member] \| Unsecured Debt [Member] \| Senior Notes May 2023 at 3.70% [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 1,200
Debt Instrument, Interest Rate, Stated Percentage	3.70%			3.70%
Debt Instrument, Maturity Date		May 31, 2023
GM Financial [Member] \| Unsecured Debt [Member] \| Senior Notes May 2019 at Floating Rates [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 400
Debt Instrument, Maturity Date		May 31, 2019
GM Financial [Member] \| Unsecured Debt [Member] \| Term Notes May 2020 at 1.168% [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount \| €				€ 500
Debt Instrument, Interest Rate, Stated Percentage	1.168%			1.168%
Debt Instrument, Maturity Date		May 31, 2020
GM Financial [Member] \| Unsecured Debt [Member] \| Senior Notes July 2021 at 3.2% [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 2,000
Debt Instrument, Interest Rate, Stated Percentage			3.20%
Debt Instrument, Maturity Date			Jul. 31, 2021