Segment and Related Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 29, 2015 Segment	Mar. 30, 2014	Dec. 31, 2013 Segment
Segment Reporting Information [Line Items]
Number of reportable segments	5		2
Net Sales	$ 453.3	$ 244.4
Income from Operations	59.9	23.6
Reportable Segments [Member]
Segment Reporting Information [Line Items]
Income from Operations	65.1	30.7
Specialty Minerals [Member] | Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	154.0	159.7
Income from Operations	23.1	21.5
Refractories [Member] | Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	73.9	84.7
Income from Operations	8.3	9.2
Performance Materials [Member] | Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	127.9	0
Income from Operations	23.8	0
Construction Technologies [Member] | Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	38.9	0
Income from Operations	4.1	0
Energy Services [Member] | Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	58.6	0
Income from Operations	$ 5.8	$ 0