Derivative Financial Instruments - Balance Sheet Location of GM Financial Unsecured Debt (Details) - GM Financial - Fair Value Hedges - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Derivatives, Fair Value [Line Items]
Carrying Amount of Hedged Items	$ 32,474	$ 35,187
Cumulative Amount of Fair Value Hedging Adjustments	1,230	693
Cumulative fair value adjustment on discontinued hedging relationships	362	428
Balance Sheet Location [Axis]: us-gaap:DebtCurrent
Derivatives, Fair Value [Line Items]
Carrying Amount of Hedged Items	3,479	4,633
Cumulative Amount of Fair Value Hedging Adjustments	21	17
Balance Sheet Location [Axis]: us-gaap:LongTermDebtAndCapitalLeaseObligations
Derivatives, Fair Value [Line Items]
Carrying Amount of Hedged Items	28,996	30,554
Cumulative Amount of Fair Value Hedging Adjustments	$ 1,209	$ 676

Derivative Liabilities, Fair Value Adjustment On Discontinued Hedging Relationships

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- Definition

Derivative Liabilities, Increase (Decrease) In Fair Value Adjustment

+ References

No definition available.

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- 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

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- Definition

Amount of liability hedged in fair value hedging relationship.

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