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Restructuring and Other Items, net (Details) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Oct. 03, 2021 USD ($) | Sep. 27, 2020 USD ($) | Jun. 28, 2020 USD ($) Mill | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Restructuring Charges [Abstract] |  |  |  |  |  |
Asset write-down charges |  |  |  | $ 0.7 | $ 7.1 | $ 7.5
Severance and other related costs |  |  |  | 0.4 | 0.5 | 5.7
Total restructuring and other items, net |  |  |  | 1.1 | 7.6 | 13.2
Restructuring Liability [Roll Forward] |  |  |  |  |  |
Restructuring liability, beginning of period |  |  |  | 3.6 | 5.0 |
Additional provisions |  |  |  | 0.1 | 0.3 |
Cash payments |  |  |  | (1.5) | (1.6) |
Other |  |  |  | 0.0 | (0.1) |
Restructuring liability, end of period |  |  |  | 2.2 | 3.6 | 5.0
Performance Materials [Member] |  |  |  |  |  |
Restructuring Charges [Abstract] |  |  |  |  |  |
Asset write-down charges |  |  |  | 0.0 | 0.0 | 5.9
Severance and other related costs |  |  |  | 0.0 | 0.0 | 2.9
Specialty Minerals [Member] |  |  |  |  |  |
Restructuring Charges [Abstract] |  |  |  |  |  |
Asset write-down charges |  |  |  | 0.7 | 7.1 | 1.6
Severance and other related costs |  |  |  | 0.4 | 0.5 | 0.9
Specialty Minerals [Member] | Paper PCC [Member] |  |  |  |  |  |
Restructuring and Other Items, Net [Abstract] |  |  |  |  |  |
Number of mills with lease terminations | Mill |  |  | 1 |  |  |
Restructuring Charges [Abstract] |  |  |  |  |  |
Asset write-down charges | $ 0.7 | $ 1.1 | $ 6.0 |  |  |
Severance and other related costs | $ 0.4 |  | $ 0.3 |  |  |
Refractories [Member] |  |  |  |  |  |
Restructuring Charges [Abstract] |  |  |  |  |  |
Severance and other related costs |  |  |  | 0.0 | 0.0 | 0.8
Corporate [Member] |  |  |  |  |  |
Restructuring Charges [Abstract] |  |  |  |  |  |
Severance and other related costs |  |  |  | $ 0.0 | $ 0.0 | $ 1.1
Verso Papers [Member] |  |  |  |  |  |
Restructuring and Other Items, Net [Abstract] |  |  |  |  |  |
Number of paper mills being idled indefinitely | Mill |  |  | 2 |  |  |

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