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Employee Benefit Plans - Schedule of amounts contributed to defined contribution plans in various jurisdictions (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plans, contributed amount	$ 29,966	$ 24,182	$ 86,893	$ 70,323
India
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plans, contributed amount	9,637	7,289	27,445	22,362
U.K.
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plans, contributed amount	5,034	4,547	14,352	13,977
China
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plans, contributed amount	6,362	4,503	18,433	11,243
Other Regions
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plans, contributed amount	3,913	3,189	11,155	8,806
U.S.
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plans, contributed amount	$ 5,020	$ 4,654	$ 15,508	$ 13,935

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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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- Definition

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+ References

No definition available.

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