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Litigation (Details) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 USD ($) Case | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Oct. 24, 2014 USD ($)
Loss Contingency, Information about Litigation Matters [Abstract] |  |  |  |
Litigation expenses | $ | $ 10.9 | $ 0.0 | $ 0.0 |
Site Contingency [Abstract] |  |  |  |
Consent decree paid by US government | $ |  |  |  | $ 2.3
Silica Cases [Member] |  |  |  |
Loss Contingency, Information about Litigation Matters [Abstract] |  |  |  |
Number of pending cases | 3 |  |  |
Cumulative number of cases dismissed | 1,493 |  |  |
Number of cases dismissed | 0 |  |  |
Number of lawsuits settled | 1 |  |  |
Number of remaining non-AMCOL cases where alleged exposure is after Company's IPO | 4 |  |  |
Number of remaining cases that involve AMCOL only - no indemnity | 4 |  |  |
Asbestos Cases [Member] |  |  |  |
Loss Contingency, Information about Litigation Matters [Abstract] |  |  |  |
Number of pending cases | 119 |  |  |
Cumulative number of cases dismissed | 64 |  |  |
Number of new cases filed | 96 |  |  |
Number of cases dismissed | 7 |  |  |
Number of lawsuits settled | 0 |  |  |
Number of cases claim liability | 49 |  |  |
Number of allege liability | 66 |  |  |
Number of cases with no alleged exposure date | 62 |  |  |
Administrative Consent Order for Contamination Associated with Historic Use of PCBs [Member] |  |  |  |
Site Contingency [Abstract] |  |  |  |
Location of plant | Canaan, Connecticut |  |  |
Estimated accrued remediation cost | $ | $ 0.4 |  |  |
Administrative Consent Order for Installation of Groundwater Contamination System [Member] |  |  |  |
Site Contingency [Abstract] |  |  |  |
Location of plant | Adams, Massachusetts plant |  |  |
Estimated accrued remediation cost | $ | $ 0.4 |  |  |
Estimated cost of wastewater treatment upgrades, lower range | $ | 6.0 |  |  |
Estimated cost of wastewater treatment upgrades, upper range | $ | $ 8.0 |  |  |

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