Debt Instrument, Renewal Term

No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

Finance Lease, Liability, Payments, Due Years Two Through Five

+ References

No definition available.

+ Details

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Namespace Prefix:	gm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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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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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Balance Type:	na
Period Type:	duration

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments for finance lease, due after fifth fiscal year following latest fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments for finance lease, due in remainder of fiscal year following latest fiscal year ended.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for finance lease.

+ References

+ Details

Name:	us-gaap_FinanceLeaseLiabilityUndiscountedExcessAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's right to use underlying asset under finance lease.

+ References

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-SubTopic 20
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-Subparagraph (a)
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of amortization expense attributable to right-of-use asset from finance lease.

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Weighted average discount rate for finance lease calculated at point in time.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Weighted average remaining lease term for finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of increase (decrease) of the credit facility.

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Balance Type:	credit
Period Type:	duration

- 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

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from a borrowing having initial term of repayment of more than three months. Includes proceeds from long-term and short-term debt.

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-Publisher FASB
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of increase in right-of-use asset obtained in exchange for finance lease liability.

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-Name Accounting Standards Codification
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Period Type:	duration

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- Details

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- Details

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- Details

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- Details

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Debt - Narrative (Details) - USD ($) $ in Millions	1 Months Ended		9 Months Ended
Debt - Narrative (Details) - USD ($) $ in Millions	Apr. 30, 2019	Jan. 31, 2019	Sep. 30, 2019	Sep. 30, 2018	Jul. 31, 2020	Dec. 31, 2018
Debt Instrument [Line Items]
Finance lease assets			$ 370
Finance lease costs			128
Finance lease right of use asset obtained in exchange for lease obligations			140
Finance lease payments for the remainder of the year			108
Years 2020 to 2023			196
Thereafter			372
Imputed interest			$ 331
Finance lease weighted-average discount rate			10.50%
Finance leas weighted average remaining lease term			12 years
Proceeds from issuance of debt (original maturities greater than three months)			$ 27,835	$ 32,801
Unsecured Debt [Member] \| Line of Credit [Member]
Debt Instrument [Line Items]
Proceeds from issuance of debt (original maturities greater than three months)			700
Unsecured Debt [Member] \| Line of Credit [Member] \| Three-Year Revolving Credit Facility January 2019 [Member]
Debt Instrument [Line Items]
Debt term		3 years
Aggregate borrowing capacity		$ 3,000
GM Financial [Member] \| Secured Debt [Member] \| Line of Credit [Member]
Debt Instrument [Line Items]
Net additional borrowing capacity, net			225
GM Financial [Member] \| Secured Debt [Member] \| Notes Payable, Other Payables [Member] \| Securitization notes payable [Member]
Debt Instrument [Line Items]
Principal amount			$ 14,200
Weighted average interest rate (percent)			2.83%
GM Financial [Member] \| Unsecured Debt [Member] \| Line of Credit [Member]
Debt Instrument [Line Items]
Debt term	364 days
Aggregate borrowing capacity	$ 2,000
Debt renewal term	364 days
GM Financial [Member] \| Unsecured Debt [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Principal amount			$ 6,500
Weighted average interest rate (percent)			3.65%
U.S. [Member] \| GM Financial [Member] \| Unsecured Debt [Member] \| Commercial Paper [Member]
Debt Instrument [Line Items]
Amounts borrowed under revolving credit facility			$ 1,000			$ 1,200
Forecast [Member] \| Unsecured Debt [Member] \| Line of Credit [Member] \| Three-Year Revolving Credit Facility January 2019 [Member]
Debt Instrument [Line Items]
Aggregate borrowing capacity					$ 2,000