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Acquisition - Summary of Unaudited Pro Forma Financial Information (Details) - Georgia-Pacific Mt. Holly LLC, Georgia-Pacific's U.S. Nonwovens Business ("Mount Holly") [Member] - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 6 Months Ended
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Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020
Business Acquisition [Line Items] |  |  |  |
Net sales | $ 254,452 | $ 241,641 | $ 501,083 | $ 498,352
Income (loss) from continuing operations | $ (919) | $ (766) | $ 7,824 | $ 8,286
Income (loss) per share from continuing operations | $ (0.02) | $ (0.02) | $ 0.17 | $ 0.19

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- Definition Amount after tax of pro forma income from continuing operations as if the business combination had been completed at the beginning of a period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(2) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(3) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 + Details
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