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Accounts Receivable, Net of Allowance for Credit Losses - Allowance for credit losses (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Provisions For Doubtful Accounts [Line Items]
Opening balance	$ 27,707	$ 29,969
Additions due to acquisitions	0	200
Additions charged/reversal released to cost and expense	2,953	3,307
Deductions/effect of exchange rate fluctuations	(1,133)	(9,954)
Closing balance	$ 29,527	27,707
Cumulative Effect, Period of Adoption, Adjustment
Provisions For Doubtful Accounts [Line Items]
Opening balance		4,185
Cumulative Effect, Period of Adoption, Adjusted Balance
Provisions For Doubtful Accounts [Line Items]
Opening balance		$ 34,154

X

- Definition

Allowance for doubtful accounts receivable charged/reversal released to cost and expense.

+ References

No definition available.

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- Definition

Allowance for Doubtful Accounts Receivable Deductions and Foreign Currency Translation Adjustments

+ References

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- Definition

Provisions for Doubtful Accounts [Line Items]

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- Definition

Amount of allowance for credit loss on accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5074-111524

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-Section 50
-Paragraph 13
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-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121599878&loc=SL82895884-210446

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- Definition

Amount of increase (decrease) in allowance for credit loss on accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447

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