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Significant Accounting Policies - Summary of Statutory Tax Rates (Detail)	12 Months Ended
	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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Reconciliation of effective tax rate.

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No definition available.

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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
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-URIDate 2020-01-01

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