Litigation (Details) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2015 USD ($) Case	Dec. 31, 2015 USD ($) Contract Load Case	Oct. 24, 2014 USD ($)	Dec. 31, 2009
Loss Contingencies [Line Items]
Number of contracts entered | Contract		2
Number of ship loads | Load		60
Default arbitration awards | $		$ 70.0
Site Contingency [Line Items]
Consent decree paid by US government | $			$ 2.3
AMCOL International Corporation [Member]
Loss Contingencies [Line Items]
Ownership interest	19.00%	19.00%		20.00%
Silica Cases [Member]
Loss Contingencies [Line Items]
Number of pending cases	30	30
Number of cases dismissed to date	1	1,465
Number of new cases filed during the quarter	0
Number of lawsuits settled		1
Asbestos Cases [Member]
Loss Contingencies [Line Items]
Number of pending cases	13	13
Number of cases dismissed to date		46
Number of new cases filed during the quarter	1
Number of lawsuits settled		0
Number of allege liability		1
Administrative Consent Order for Contamination Associated with Historic Use of PCBs [Member]
Site Contingency [Line Items]
Location of plant		Canaan, Connecticut
Estimated accrued remediation cost | $	$ 0.4	$ 0.4
Administrative Consent Order for Installation of Groundwater Contamination System [Member]
Site Contingency [Line Items]
Location of plant		Adams, Massachusetts plant
Estimated accrued remediation cost | $	$ 0.4	$ 0.4
Estimated cost of wastewater treatment upgrades, lower range | $		6.0
Estimated cost of wastewater treatment upgrades, upper range | $		$ 8.0