Estimated cost of upgrades to operate the Company's wastewater treatment facilities at its Adams, Massachusetts plant.

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Cumulative number of claims dismissed.

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Cumulative amount of litigation expense incurred, including but not limited to legal, forensic, accounting, and investigative fees.

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Number of cases claim subject to indemnification, in whole or in part, because the plaintiffs claim liability based on sales of products that occurred either entirely before the initial public offering, or both before and after the initial public offering.

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Number of remaining cases.

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Number of remaining cases where alleged exposure occurred after the Company's initial public offering (IPO).

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Number of remaining cases subject to indemnity in part until dates of exposure.

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Number of remaining cases with no available indemnity.

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

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Amount awarded to other party in judgment or settlement of litigation.

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Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

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Number of claims dismissed.

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Number of claims settled.

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The total number of new claims filed pertaining to a loss contingency during the period.

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Number of pending claims pertaining to a loss contingency.

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Amount of the estimated recovery from third parties recorded in the period for an individual site that reduces environmental remediation expense.

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Contingencies (Details) $ in Millions	3 Months Ended		6 Months Ended
Contingencies (Details) $ in Millions	Jun. 28, 2020 USD ($) Case	Dec. 31, 2014 USD ($)	Jun. 28, 2020 USD ($) Case
Silica Cases [Member]
Contingencies [Abstract]
Number of pending cases	3		3
Cumulative number of cases dismissed	1,493		1,493
Number of cases dismissed	0
Number of lawsuits settled			1
Asbestos Cases [Member]
Contingencies [Abstract]
Number of pending cases	176		176
Cumulative number of cases dismissed	83		83
Number of new cases filed	46
Number of cases dismissed	5
Number of lawsuits settled			0
Non-AMCOL Asbestos Cases [Member]
Contingencies [Abstract]
Number of cases subject to indemnification	136		136
Number of remaining cases subject to indemnity until dates of exposure	33		33
Number of remaining cases	38		38
Number of remaining cases alleging exposure occurred after initial public offering	5		5
AMCOL Asbestos Cases [Member]
Contingencies [Abstract]
Number of remaining cases with no available indemnity	2		2
Bankruptcy Estate of Novinda [Member]
Contingencies [Abstract]
Damages, interest and costs awarded to Novinda in arbitration \| $	$ 8.0
Total litigation expenses \| $	11.8		$ 11.8
Litigation expense \| $			0.9
Canaan, Connecticut Plant [Member]
Site Contingency [Abstract]
Consent decree paid by US government \| $		$ 2.3
Accrued remediation costs \| $	0.4		0.4
Adams, Massachusetts Plant [Member]
Site Contingency [Abstract]
Accrued remediation costs \| $	0.4		0.4
Adams, Massachusetts Plant [Member] \| Minimum [Member]
Site Contingency [Abstract]
Estimated cost of wastewater treatment upgrades \| $	6.0		6.0
Adams, Massachusetts Plant [Member] \| Maximum [Member]
Site Contingency [Abstract]
Estimated cost of wastewater treatment upgrades \| $	$ 8.0		$ 8.0