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Pensions and Post-Employment Benefits - Sensitivity Analysis of Pension and Other Post-Employment Benefits (Detail) $ in Millions | Dec. 31, 2020 USD ($)
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Actuarial assumption of discount rates [member] |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Sensitivity, possible increase in actuarial assumption | $ (207)
Sensitivity, possible decrease in actuarial assumption | 234
Actuarial assumption of expected rates of salary increases [member] |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Sensitivity, possible increase in actuarial assumption | 8
Sensitivity, possible decrease in actuarial assumption | (7)
Actuarial assumption of expected rates of pension increases [member] |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Sensitivity, possible increase in actuarial assumption | 146
Sensitivity, possible decrease in actuarial assumption | (128)
Pension defined benefit plans [member] | Actuarial assumption of discount rates [member] |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Sensitivity, possible increase in actuarial assumption | (202)
Sensitivity, possible decrease in actuarial assumption | 228
Pension defined benefit plans [member] | Actuarial assumption of expected rates of salary increases [member] |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Sensitivity, possible increase in actuarial assumption | 7
Sensitivity, possible decrease in actuarial assumption | (7)
Pension defined benefit plans [member] | Actuarial assumption of expected rates of pension increases [member] |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Sensitivity, possible increase in actuarial assumption | 146
Sensitivity, possible decrease in actuarial assumption | (128)
Other post employment benefits [Member] | Actuarial assumption of discount rates [member] |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Sensitivity, possible increase in actuarial assumption | (5)
Sensitivity, possible decrease in actuarial assumption | 6
Other post employment benefits [Member] | Actuarial assumption of expected rates of salary increases [member] |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Sensitivity, possible increase in actuarial assumption | $ 1

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- Definition The increase (decrease) in a defined benefit obligation that would have been caused by a decrease in a significant actuarial assumption that was reasonably possible at the end of the reporting period. [Refer: Actuarial assumptions [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 145 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_145_a&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The increase (decrease) in a defined benefit obligation that would have been caused by an increase in a significant actuarial assumption that was reasonably possible at the end of the reporting period. [Refer: Actuarial assumptions [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 145 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_145_a&doctype=Standard -URIDate 2020-01-01 + Details
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