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Acquisition - Summary of Pro Forma Financial Information (Details) - Georgia-Pacific Mt. Holly LLC, Georgia-Pacific's U.S. Nonwovens Business ("Mount Holly") - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Business Acquisition [Line Items] |  |  |
Net sales | $ 260,722 | $ 750,236 | $ 759,074
Income from continuing operations | $ 7,279 | $ 15,339 | $ 15,565
Income (loss) per share from continuing operations, basic (in dollars per share) | $ 0.16 | $ 0.34 | $ 0.35
Income (loss) per share from continuing operations, diluted (in dollars per share) | $ 0.16 | $ 0.34 | $ 0.35

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