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Significant Accounting Policies - Effects of Inflation (Detail) | 12 Months Ended | 36 Months Ended
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Dec. 31, 2020 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disclosure of Hyperinflationary Reporting [line items] |  |  |  |
Cumulative inflation percentage, threshold for recognition | 100.00% |  |  |
Mexico [member] |  |  |  |
Disclosure of Hyperinflationary Reporting [line items] |  |  |  |
Cumulative inflation percentage, actual, during the period |  | 11.20% | 13.20% | 15.70%
Guatemala [member] |  |  |  |
Disclosure of Hyperinflationary Reporting [line items] |  |  |  |
Cumulative inflation percentage, actual, during the period |  | 10.90% | 11.80% | 12.20%
Costa Rica [member] |  |  |  |
Disclosure of Hyperinflationary Reporting [line items] |  |  |  |
Cumulative inflation percentage, actual, during the period |  | 4.50% | 5.80% | 5.70%
Panama [member] |  |  |  |
Disclosure of Hyperinflationary Reporting [line items] |  |  |  |
Cumulative inflation percentage, actual, during the period |  | (1.50%) | 0.50% | 2.10%
Colombia [member] |  |  |  |
Disclosure of Hyperinflationary Reporting [line items] |  |  |  |
Cumulative inflation percentage, actual, during the period |  | 8.80% | 11.00% | 13.40%
Nicaragua [member] |  |  |  |
Disclosure of Hyperinflationary Reporting [line items] |  |  |  |
Cumulative inflation percentage, actual, during the period |  | 13.50% | 15.60% | 13.10%
Argentina [member] |  |  |  |
Disclosure of Hyperinflationary Reporting [line items] |  |  |  |
Cumulative inflation percentage, actual, during the period |  | 209.20% | 179.40% | 158.40%
Brazil [member] |  |  |  |
Disclosure of Hyperinflationary Reporting [line items] |  |  |  |
Cumulative inflation percentage, actual, during the period |  | 13.10% | 11.10% | 25.00%
Philippines [member] |  |  |  |
Disclosure of Hyperinflationary Reporting [line items] |  |  |  |
Cumulative inflation percentage, actual, during the period |  |  |  | 11.90%
United States [member] |  |  |  |
Disclosure of Hyperinflationary Reporting [line items] |  |  |  |
Cumulative inflation percentage, actual, during the period |  | 3.70% |  |
Euro Zone [member] |  |  |  |
Disclosure of Hyperinflationary Reporting [line items] |  |  |  |
Cumulative inflation percentage, actual, during the period |  | 2.40% | 3.60% | 2.70%
Chile [member] |  |  |  |
Disclosure of Hyperinflationary Reporting [line items] |  |  |  |
Cumulative inflation percentage, actual, during the period |  | 8.80% | 8.30% | 9.70%
Peru [member] |  |  |  |
Disclosure of Hyperinflationary Reporting [line items] |  |  |  |
Cumulative inflation percentage, actual, during the period |  | 6.20% | 5.20% | 9.30%
Ecuador [member] |  |  |  |
Disclosure of Hyperinflationary Reporting [line items] |  |  |  |
Cumulative inflation percentage, actual, during the period |  | (0.70%) | 0.30% | 30.30%
Uruguay [member] |  |  |  |
Disclosure of Hyperinflationary Reporting [line items] |  |  |  |
Cumulative inflation percentage, actual, during the period |  | 28.50% | 22.00% | 25.30%

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