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Acquisition, Restructuring and Management Fee Costs - Summary of Total Acquisition, Restructuring and Management Fee Costs (Parenthetical) (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
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Sep. 26, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Sentinel Capital Partners [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Aacquisition costs and management fees | $ 23,275 | $ 6,089 | $ 3,662 | $ 12,869

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