Segment and Related Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 28, 2014	Sep. 29, 2013	Sep. 28, 2014 Segment	Sep. 29, 2013 Segment	Dec. 31, 2013 Segment
Segment Reporting Information [Line Items]
Number of reportable segments			5	2	2
Net Sales	$ 543.5	$ 254.2	$ 1,209.0	$ 761.5
Income from Operations	66.8	32.7	126.2	93.4
Reportable Segments [Member]
Segment Reporting Information [Line Items]
Income from Operations	72.9	34.4	148.5	98.2
Specialty Minerals [Member] | Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	163.0	167.4	490.5	502.5
Income from Operations	26.0	26.0	71.4	74.4
Refractories [Member] | Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	90.4	86.8	266.8	259.0
Income from Operations	9.7	8.4	29.0	23.8
Performance Materials [Member] | Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	135.6	0	211.4	0
Income from Operations	18.7	0	23.0	0
Construction Technologies [Member] | Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	69.1	0	106.3	0
Income from Operations	8.3	0	9.0	0
Energy Services [Member] | Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	85.4	0	134.0	0
Income from Operations	$ 10.2	$ 0	$ 16.1	$ 0