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Employee Benefit Plans - Amounts Contributed to Defined Contribution Plans in Various Jurisdictions (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plans, contributed amount	$ 21,635	$ 19,156
India
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plans, contributed amount	8,201	6,565
U.K.
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plans, contributed amount	2,973	2,423
China
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plans, contributed amount	3,923	4,773
Other Regions
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plans, contributed amount	2,115	1,069
U.S.
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plans, contributed amount	$ 4,423	$ 4,326

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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

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+ References

No definition available.

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