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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 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 + Details
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