Debt - Narrative (Details) - USD ($) $ in Billions	1 Months Ended	9 Months Ended
Mar. 31, 2024	Sep. 30, 2024
Unsecured Debt \| Delayed Draw Term Loan Credit Agreement
Debt Instrument [Line Items]
Debt term	364 days
Aggregate borrowing capacity	$ 3.0
Unsecured Debt \| GM Financial \| Senior Notes
Debt Instrument [Line Items]
Principal amount		$ 12.4
Weighted average interest rate (percent)		5.40%
Unsecured Debt \| GM Financial \| $2.0 Billion Dollar Revolving Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Debt term	364 days	364 days
Aggregate borrowing capacity	$ 2.0	$ 2.0
Secured Debt \| GM Financial \| Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Increase to maximum borrowing capacity		24.2
Secured Debt \| GM Financial \| Securitization Notes Payable \| Notes Payable, Other Payables
Debt Instrument [Line Items]
Principal amount		$ 18.0
Weighted average interest rate (percent)		5.50%

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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.

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Weighted average interest rate of debt outstanding.

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Amount of increase (decrease) of the credit facility.

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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.

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