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Other Expense, Net - Summary Of Net Losses Or Gains On Investments (Detail) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021
Gain (Loss) on Securities [Line Items] |  |
Unrealized gain on investment revaluation | $ 110 | $ (63)
Other expense, net | 221 | 2
Tax effect | (53) | 7
Net loss attributable to Magna | 168 | 9
Public Company Warrants [Member] |  |
Gain (Loss) on Securities [Line Items] |  |
Unrealized gain on investment revaluation | 173 | (4)
Public and Private Equity Investments [Member] |  |
Gain (Loss) on Securities [Line Items] |  |
Unrealized gain on investment revaluation | 49 | $ 6
Public Equity Investments [Member] |  |
Gain (Loss) on Securities [Line Items] |  |
Unrealized gain on investment revaluation | $ (1) |

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