Derivative Financial Instruments - Balance Sheet Location of GM Financial Unsecured Debt (Details) - Fair Value Hedges - GM Financial - USD ($) $ in Millions |
Jun. 30, 2022 |
Dec. 31, 2021 |
|---|---|---|
| Derivatives, Fair Value [Line Items] | ||
| Carrying Amount of Hedged Items | $ 28,646 | $ 24,964 |
| Cumulative Amount of Fair Value Hedging Adjustments on Hedging Relationships | 454 | (226) |
| Short-term unsecured debt | ||
| Derivatives, Fair Value [Line Items] | ||
| Carrying Amount of Hedged Items | 3,042 | 1,338 |
| Cumulative Amount of Fair Value Hedging Adjustments on Hedging Relationships | 8 | (1) |
| Long-term unsecured debt | ||
| Derivatives, Fair Value [Line Items] | ||
| Carrying Amount of Hedged Items | 25,604 | 23,626 |
| Cumulative Amount of Fair Value Hedging Adjustments on Hedging Relationships | $ 446 | (225) |
| Cumulative fair value adjustment on discontinued hedging relationships | $ 246 |