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Other Expense, Net - Summary of Impairment Charges and Loss on Sale Recorded for Certain Investments (Parenthetical) (Detail) - Dongfeng Getrag Transmission Co. Ltd ["DGT"] [Member] - Disposal Group, Not Discontinued Operations [Member] $ in Millions | 12 Months Ended
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Dec. 31, 2020 USD ($)
Impairments and loss on sale of equity-accounted investments [Line Items] |
Equity method investment realized gain loss on disposal | $ 10
Equity method investment realized gain loss on disposal after tax | $ 10
Percentage of equity method investment sold | 50.00%

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