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v3.21.1

Employee Benefits - Summary of Assumptions Used in Determining the Net Period Cost (Detail) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Puerto Rico [member] |  |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |  |
Discount rate and long-term rate return | 2.34% | 3.23% | 4.45%
Rate of future salary increases | 2.75% | 2.75% | 2.75%
Percentage of increase in health care costs for the coming year | 2.28% | 3.18% | 3.87%
Brazil [member] |  |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |  |
Discount rate and long-term rate return |  | 7.03% | 9.10%
Rate of future salary increases | 3.25% | 3.80% | 4.00%
Percentage of increase in health care costs for the coming year | 9.96% | 10.30% | 10.50%
Year to which this level will be maintained | 2031 | 2029 | 2029
Brazil [member] | Bottom of range [member] |  |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |  |
Discount rate and long-term rate return | 6.48% |  |
Brazil [member] | Top of range [member] |  |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |  |
Discount rate and long-term rate return | 7.39% |  |
Mexico [member] |  |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |  |
Discount rate and long-term rate return | 10.04% | 10.50% | 11.81%
Rate of future salary increases | 2.84% | 3.20% | 3.55%
Europe [member] |  |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |  |
Rate of increase of pensions | 1.60% | 1.60% | 1.60%
Europe [member] | Bottom of range [member] |  |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |  |
Employee turnover rate | 0.00% | 0.00% | 0.00%
Europe [member] | Top of range [member] |  |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |  |
Employee turnover rate | 1.31% | 1.38% | 1.51%
Europe [member] | Actuarial assumption rate one [member] |  |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |  |
Discount rate and long-term rate return | 0.25% | 0.75% | 1.25%
Rate of future salary increases | 3.00% | 3.00% | 3.00%
Europe [member] | Actuarial assumption rate two [member] |  |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |  |
Discount rate and long-term rate return | 0.50% | 1.00% | 1.75%
Rate of future salary increases | 3.50% | 3.50% | 3.50%
Europe [member] | Actuarial assumption rate three [member] |  |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |  |
Discount rate and long-term rate return | 0.75% | 1.25% | 2.00%
Rate of future salary increases | 4.10% | 4.40% | 4.40%

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