Segment and Related Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 29, 2014	Jun. 30, 2013	Jun. 29, 2014 Segment	Jun. 30, 2013 Segment
Segment Reporting Information [Line Items]
Number of reportable segments			5	2
Net Sales	$ 421.1	$ 256.8	$ 665.5	$ 507.4
Income from Operations	44.9	33.7	75.6	63.9
Specialty Minerals [Member] | Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	167.9	168.3	327.5	335.3
Income from Operations	23.9	25.2	45.4	48.5
Refractories [Member] | Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	91.6	88.5	176.4	172.1
Income from Operations	10.1	8.5	19.3	15.4
Performance Materials [Member] | Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	75.8	0	75.8	0
Income from Operations	4.3	0	4.3	0
Construction Technologies [Member] | Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	37.2	0	37.2	0
Income from Operations	0.7	0	0.7	0
Energy Services [Member] | Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	48.6	0	48.6	0
Income from Operations	$ 5.9	$ 0	$ 5.9	$ 0