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v3.21.1

Significant Accounting Policies - Summary of Statutory Tax Rates (Detail) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Reconciliation of Effective Tax Rate [Line Items] |  |  |
Applicable tax rate | 30.00% | 30.00% | 30.00%
Mexico [member] |  |  |
Reconciliation of Effective Tax Rate [Line Items] |  |  |
Applicable tax rate | 30.00% | 30.00% | 30.00%
United States [member] |  |  |
Reconciliation of Effective Tax Rate [Line Items] |  |  |
Applicable tax rate | 21.00% | 21.00% | 21.00%
United Kingdom [member] |  |  |
Reconciliation of Effective Tax Rate [Line Items] |  |  |
Applicable tax rate | 19.00% | 19.30% | 19.30%
France [member] |  |  |
Reconciliation of Effective Tax Rate [Line Items] |  |  |
Applicable tax rate | 32.00% | 34.40% | 34.40%
Germany [member] |  |  |
Reconciliation of Effective Tax Rate [Line Items] |  |  |
Applicable tax rate | 28.20% | 28.20% | 28.20%
Spain [member] |  |  |
Reconciliation of Effective Tax Rate [Line Items] |  |  |
Applicable tax rate | 25.00% | 25.00% | 25.00%
Philippines [member] |  |  |
Reconciliation of Effective Tax Rate [Line Items] |  |  |
Applicable tax rate | 30.00% | 30.00% | 30.00%
Colombia [member] |  |  |
Reconciliation of Effective Tax Rate [Line Items] |  |  |
Applicable tax rate | 32.00% | 33.00% | 37.00%
Bottom of range [member] | Other [member] |  |  |
Reconciliation of Effective Tax Rate [Line Items] |  |  |
Applicable tax rate | 9.00% | 7.80% | 7.80%
Top of range [member] | Other [member] |  |  |
Reconciliation of Effective Tax Rate [Line Items] |  |  |
Applicable tax rate | 30.00% | 35.00% | 39.00%

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- Definition The applicable income tax rate. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2020-01-01 -Paragraph 81 -Subparagraph c -Clause ii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=12&code=ifrs-tx-2020-en-r&anchor=para_81_c_ii&doctype=Standard -URIDate 2020-01-01 + Details
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