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Other Assets - Summary of Other Assets (Detail) - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019
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Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract] |  |
Preproduction costs related to long-term supply agreements | $ 694 | $ 683
Long-term receivables | 209 | 217
Unrealized gain on cash flow hedges [note 21] | 16 | 24
Pension overfunded status [note 17[a]] | 4 | 22
Other, net | 40 | 50
Total other assets | $ 963 | $ 996

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