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Long-Term Employee Benefit Liabilities - Future Benefit Payments (Detail) $ in Millions | Dec. 31, 2019 USD ($)
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Defined Benefit Plan Disclosure [Line Items] |
Expected employer contributions - 2020 | $ 22
2020 | 33
2021 | 35
2022 | 35
2023 | 39
2024 | 43
Thereafter | 250
Total | 435
Pension Plan, Defined Benefit [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Expected employer contributions - 2020 | 11
2020 | 22
2021 | 22
2022 | 23
2023 | 23
2024 | 24
Thereafter | 131
Total | 245
Termination and Long Service Arrangements [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Expected employer contributions - 2020 | 9
2020 | 10
2021 | 11
2022 | 11
2023 | 14
2024 | 18
Thereafter | 119
Total | 183
Retirement Medical Benefits Plans [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Expected employer contributions - 2020 | 2
2020 | 1
2021 | 2
2022 | 2
2023 | 2
2024 | 2
Thereafter | 8
Total | $ 17

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