Debt Instrument, Renewal Term

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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

- Definition

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

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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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- 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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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

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-Name Accounting Standards Codification
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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.

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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

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

- Definition

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

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+ Details

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

- Definition

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

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- 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.

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- 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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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

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Automotive and GM Financial Debt Narrative (Details) - USD ($) $ in Millions	1 Months Ended
	Apr. 30, 2019	Jan. 31, 2019	Jul. 31, 2020	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Finance lease assets				$ 314
Finance lease payments for the remainder of the year				106
Years 2020 to 2023				160
Thereafter				371
Imputed interest				$ 346
Finance lease weighted-average discount rate				11.90%
Finance leas weighted average remaining lease term				14 years 7 months 6 days
Unsecured Debt [Member] \| Line of Credit [Member]
Debt Instrument [Line Items]
Aggregate borrowing capacity		$ 3,000
Amounts borrowed under revolving credit facility				$ 400
Unsecured Debt [Member] \| Line of Credit [Member] \| Three-Year Revolving Credit Facility January 2019 [Member]
Debt Instrument [Line Items]
Debt term		3 years
GM Financial [Member] \| Secured Debt [Member] \| Notes Payable, Other Payables [Member] \| Securitization notes payable [Member]
Debt Instrument [Line Items]
Principal amount				$ 4,600
Weighted average interest rate (percent)				3.16%
GM Financial [Member] \| Unsecured Debt [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Principal amount				$ 3,900
Weighted average interest rate (percent)				4.22%
U.S. [Member] \| GM Financial [Member] \| Unsecured Debt [Member] \| Commercial Paper [Member]
Debt Instrument [Line Items]
Amounts borrowed under revolving credit facility				$ 1,500	$ 1,200
Subsequent Event [Member] \| GM Financial [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Principal amount	$ 1,300
Weighted average interest rate (percent)	3.55%
Subsequent Event [Member] \| 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
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