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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
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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 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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