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Commitments and Contingencies (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2016	Jun. 30, 2020
Commitments And Contingencies [Line Items]
Bank guarantees and letters of credits, outstanding	$ 6,223	$ 10,156
Income tax examination, assessed tax, affiliate			$ 110,155
Income tax examination, amount yet to be refunded to the Company	26,839
Affiliated Entity
Commitments And Contingencies [Line Items]
Refunds challenged by taxing authority, amount				$ 21,727
Capital Addition Purchase Commitments
Commitments And Contingencies [Line Items]
Commitments and contingencies	$ 9,609	$ 5,128

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- Definition

Commitments And Contingencies [Line Items]

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Income Tax Examination, Refund From Settlement With Taxing Authority, Yet To Be Refunded

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Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

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- Definition

Estimated amount of loss resulting from an adverse tax position.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (d)(3)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319

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The minimum amount the entity agreed to spend under the long-term purchase commitment.

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