Restructuring Charges (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 28, 2014	Sep. 29, 2013	Sep. 28, 2014	Sep. 29, 2013
Restructuring Cost and Reserve [Line Items]
Restructuring Charges Total	$ 5.8	$ 0	$ 11.8	$ 0
Reduction in workforce (in hundredths)	8.00%		8.00%
Annualized savings from reduction of workforce			20
Restructuring liability, beginning of period			0
Additional provisions	5.8	0	11.8	0
Cash payments			(0.6)
Restructuring liability, end of period	11.2		11.2
Reportable Segments [Member] | Specialty Minerals [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges Total	0.5		2.7
Additional provisions	0.5		2.7
Reportable Segments [Member] | Refractories [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges Total	0		0.6
Additional provisions	0		0.6
Reportable Segments [Member] | Performance Materials [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges Total	2.0		3.2
Additional provisions	2.0		3.2
Reportable Segments [Member] | Construction Technologies [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges Total	2.0		3.0
Additional provisions	2.0		3.0
Reportable Segments [Member] | Energy Services [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges Total	1.3		2.3
Additional provisions	$ 1.3		$ 2.3