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Financial Instruments - Foreign Exchange Forward Contracts Representing Commitments to Buy and Sell Various Foreign Currencies (Detail) - 12 months ended Dec. 31, 2020 Kč in Millions, $ in Millions, $ in Millions | USD ($) | MXN ($) | CZK (Kč)
--- | --- | --- | ---
Canada, Dollars |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Sell Contracts) | $ (1,115) |  |
Canada, Dollars | 2021 [Member] | US Dollar [Member] |  |  |
Derivative [Line Items] |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 1.30755 |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.75821 |  |
Canada, Dollars | 2021 [Member] | Long [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Buy Contracts) | $ 131 |  |
Canada, Dollars | 2021 [Member] | Short [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Sell Contracts) | $ (823) |  |
Canada, Dollars | 2022 [Member] | US Dollar [Member] |  |  |
Derivative [Line Items] |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 1.32628 |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.76478 |  |
Canada, Dollars | 2022 [Member] | Long [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Buy Contracts) | $ 12 |  |
Canada, Dollars | 2022 [Member] | Short [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Sell Contracts) | $ (339) |  |
Canada, Dollars | 2023 [Member] | US Dollar [Member] |  |  |
Derivative [Line Items] |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 1.32885 |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.75963 |  |
Canada, Dollars | 2023 [Member] | Long [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Buy Contracts) | $ 2 |  |
Canada, Dollars | 2023 [Member] | Short [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Sell Contracts) | (71) |  |
Canada, Dollars | 2024 [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Sell Contracts) | $ (22) |  |
Canada, Dollars | 2024 [Member] | US Dollar [Member] |  |  |
Derivative [Line Items] |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.75896 |  |
Canada, Dollars | 2025 [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Sell Contracts) | $ (5) |  |
Canada, Dollars | 2025 [Member] | US Dollar [Member] |  |  |
Derivative [Line Items] |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.77039 |  |
United States of America, Dollars |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Buy Contracts) |  | $ 6,316 |
United States of America, Dollars | 2021 [Member] | Mexican Peso [Member] |  |  |
Derivative [Line Items] |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.04523 |  |
United States of America, Dollars | 2021 [Member] | Long [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Buy Contracts) |  | 4,077 |
United States of America, Dollars | 2022 [Member] | Mexican Peso [Member] |  |  |
Derivative [Line Items] |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.04650 |  |
United States of America, Dollars | 2022 [Member] | Long [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Buy Contracts) |  | 1,746 |
United States of America, Dollars | 2023 [Member] | Mexican Peso [Member] |  |  |
Derivative [Line Items] |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.04540 |  |
United States of America, Dollars | 2023 [Member] | Long [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Buy Contracts) |  | $ 493 |
Euro Member Countries, Euro |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Buy Contracts) | $ 110 |  | Kč 6,482
Euro Member Countries, Euro | 2021 [Member] | US Dollar [Member] |  |  |
Derivative [Line Items] |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.82728 |  |
Foreign exchange forward contract, Sales Exchange Rate | 1.18543 |  |
Euro Member Countries, Euro | 2021 [Member] | Czech Koruna [Member] |  |  |
Derivative [Line Items] |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.03773 |  |
Euro Member Countries, Euro | 2021 [Member] | Long [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Buy Contracts) | $ 171 |  | 4,053
Euro Member Countries, Euro | 2021 [Member] | Short [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Sell Contracts) | $ (97) |  |
Euro Member Countries, Euro | 2022 [Member] | US Dollar [Member] |  |  |
Derivative [Line Items] |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.81888 |  |
Foreign exchange forward contract, Sales Exchange Rate | 1.19120 |  |
Euro Member Countries, Euro | 2022 [Member] | Czech Koruna [Member] |  |  |
Derivative [Line Items] |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.03770 |  |
Euro Member Countries, Euro | 2022 [Member] | Long [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Buy Contracts) | $ 62 |  | 2,099
Euro Member Countries, Euro | 2022 [Member] | Short [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Sell Contracts) | $ (35) |  |
Euro Member Countries, Euro | 2023 [Member] | US Dollar [Member] |  |  |
Derivative [Line Items] |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.81565 |  |
Foreign exchange forward contract, Sales Exchange Rate | 1.22051 |  |
Euro Member Countries, Euro | 2023 [Member] | Czech Koruna [Member] |  |  |
Derivative [Line Items] |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.03714 |  |
Euro Member Countries, Euro | 2023 [Member] | Long [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Buy Contracts) | $ 32 |  | Kč 330
Euro Member Countries, Euro | 2023 [Member] | Short [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Sell Contracts) | $ (27) |  |
Euro Member Countries, Euro | 2024 [Member] | US Dollar [Member] |  |  |
Derivative [Line Items] |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.82558 |  |
Foreign exchange forward contract, Sales Exchange Rate | 1.25793 |  |
Euro Member Countries, Euro | 2024 [Member] | Long [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Buy Contracts) | $ 10 |  |
Euro Member Countries, Euro | 2024 [Member] | Short [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount (Sell Contracts) | $ (6) |  |

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