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v3.20.2

Restructuring and Other Items, net (Details) $ in Millions | 1 Months Ended | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
Aug. 31, 2020 USD ($) | Jun. 30, 2020 USD ($) Mill | Sep. 27, 2020 USD ($) | Sep. 29, 2019 USD ($) | Jun. 30, 2019 USD ($) | Sep. 27, 2020 USD ($) | Sep. 29, 2019 USD ($)
Restructuring Charges [Abstract] |  |  |  |  |  |  |
Impairment of assets |  |  | $ 1.1 | $ 0.0 | $ 7.5 | $ 7.1 | $ 7.5
Severance and other employee costs |  |  | 0.3 | 0.0 | $ 5.7 | 0.6 | 5.7
Total restructuring and other items, net |  |  | 1.5 | 0.0 |  | 8.0 | 13.2
Restructuring Reserve [Roll Forward] |  |  |  |  |  |  |
Restructuring liability, beginning of period |  |  |  |  |  | 5.0 |
Additional provision |  |  |  |  |  | 0.3 |
Cash payments |  |  |  |  |  | (1.2) |
Restructuring liability, ending of period |  |  | 4.1 |  |  | 4.1 |
Performance Materials [Member] |  |  |  |  |  |  |
Restructuring Charges [Abstract] |  |  |  |  |  |  |
Impairment of assets |  |  | 0.0 | 0.0 |  | 0.0 | 4.2
Severance and other employee costs |  |  | 0.0 | 0.0 |  | 0.0 | 2.8
Specialty Minerals [Member] |  |  |  |  |  |  |
Restructuring Charges [Abstract] |  |  |  |  |  |  |
Impairment of assets |  |  | 1.1 | 0.0 |  | 7.1 | 1.6
Severance and other employee costs |  |  | 0.3 | 0.0 |  | 0.6 | 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] |  |  |  |  |  |  |
Impairment of assets | $ 1.1 | $ 6.0 |  |  |  |  |
Severance and other employee costs |  | $ 0.3 |  |  |  |  |
Refractories [Member] |  |  |  |  |  |  |
Restructuring Charges [Abstract] |  |  |  |  |  |  |
Severance and other employee costs |  |  | 0.0 | 0.0 |  | 0.0 | 0.8
Energy Services [Member] |  |  |  |  |  |  |
Restructuring Charges [Abstract] |  |  |  |  |  |  |
Impairment of assets |  |  | 0.0 | 0.0 |  | 0.0 | 1.7
Severance and other employee costs |  |  | 0.0 | 0.0 |  | 0.0 | 0.1
Corporate [Member] |  |  |  |  |  |  |
Restructuring Charges [Abstract] |  |  |  |  |  |  |
Severance and other employee costs |  |  | 0.0 | 0.0 |  | 0.0 | 1.1
Other |  |  | $ 0.1 | $ 0.0 |  | $ 0.3 | $ 0.0
Verso Papers [Member] |  |  |  |  |  |  |
Restructuring and Other Items, Net [Abstract] |  |  |  |  |  |  |
Number of paper mills being idled indefinitely | Mill |  | 2 |  |  |  |  |

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