Contract Assets and Liabilities - Additional Information (Detail) - USD ($) $ in Thousands |
Sep. 30, 2021 |
Dec. 31, 2020 |
Jan. 01, 2020 |
Dec. 31, 2019 |
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| Contract with Customer, Liability [Abstract] | ||||
| Contract liabilities - current | $ 14,453 | $ 14,537 | $ 8,200 | $ 7,952 |
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- References No definition available.
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- Definition Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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