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Restructuring - Summary of Restructuring Charges (Details) - Composite Fibers $ in Thousands | 12 Months Ended
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Dec. 31, 2020 USD ($)
Restructuring Cost And Reserve [Line Items] |
Severance and benefit continuation | $ 6,143
Accelerated depreciation | 3,900
Inventory and spare parts | 977
Other | 91
Total | $ 11,111

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