Segment and Related Information, Sales By Product Category (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 03, 2021	Sep. 27, 2020	Oct. 03, 2021	Sep. 27, 2020
Segment and Related Information [Abstract]
Net sales	$ 473.2	$ 388.3	$ 1,381.4	$ 1,163.0
Metalcasting [Member]
Segment and Related Information [Abstract]
Net sales	72.9	66.3	235.0	180.8
Household, Personal Care & Specialty Products [Member]
Segment and Related Information [Abstract]
Net sales	121.8	93.9	333.9	278.0
Environmental Products [Member]
Segment and Related Information [Abstract]
Net sales	39.8	30.2	105.8	104.5
Building Materials [Member]
Segment and Related Information [Abstract]
Net sales	15.9	13.5	45.0	43.5
Paper PCC [Member]
Segment and Related Information [Abstract]
Net sales	89.5	74.5	264.9	225.1
Specialty PCC [Member]
Segment and Related Information [Abstract]
Net sales	18.2	17.3	57.1	49.7
Ground Calcium Carbonate [Member]
Segment and Related Information [Abstract]
Net sales	25.0	23.2	74.5	66.4
Talc [Member]
Segment and Related Information [Abstract]
Net sales	14.2	10.1	40.9	30.8
Refractory Products [Member]
Segment and Related Information [Abstract]
Net sales	58.3	48.8	175.1	151.7
Metallurgical Products [Member]
Segment and Related Information [Abstract]
Net sales	$ 17.6	$ 10.5	$ 49.2	$ 32.5