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Acquisition - Narrative (Details) t in Thousands, $ in Thousands |  | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
May 13, 2021 USD ($) employee t | Sep. 30, 2021 USD ($) | Sep. 30, 2021 USD ($) | Dec. 31, 2020 USD ($)
Business Acquisition [Line Items] |  |  |  |
Goodwill |  | $ 191,619 | $ 191,619 | $ 164,369
Intangible assets, net |  | 90,709 | 90,709 | 81,835
Georgia-Pacific Mt. Holly LLC, Georgia-Pacific's U.S. Nonwovens Business ("Mount Holly") |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Business acquisition purchase price | $ 170,900 |  |  |
Annual production capacity | t | 37 |  |  |
Number of employees employed | employee | 140 |  |  |
Annual sales of acquiree |  |  |  | $ 100,000
Acquired intangible assets estimated remaining life | 11 years |  |  |
Goodwill | $ 36,231 |  |  |
Intangible assets, net | $ 20,000 |  |  |
Goodwill deductible for tax purposes, period | 15 years |  |  |
Pro forma revenue of acquiree |  |  | 34,200 |
Pro forma operating income of acquiree |  |  | 4,000 |
One-time costs |  | $ 200 | $ 4,600 |
Georgia-Pacific Mt. Holly LLC, Georgia-Pacific's U.S. Nonwovens Business ("Mount Holly") | Minimum |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Acquired property, plant and equipment estimated remaining lives | 5 years |  |  |
Georgia-Pacific Mt. Holly LLC, Georgia-Pacific's U.S. Nonwovens Business ("Mount Holly") | Maximum |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Acquired property, plant and equipment estimated remaining lives | 35 years |  |  |

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