Revenue from Contracts with Customers (Tables)

9 Months Ended

Sep. 30, 2018

Revenue from Contracts with Customers [Abstract]

Disaggregation of Revenue

The following table disaggregates our revenue by major source (product line) for the three and nine month periods ended September 30, 2018 and October 1, 2017 :

(millions of dollars)	Three Months Ended				Nine Months Ended
Net Sales	Sep. 30, 2018		Oct. 1, 2017		Sep. 30, 2018		Oct. 1, 2017
Metalcasting	$	77.8	$	73.6	$	245.8	$	215.9
Household, Personal Care and Specialty Products		71.9		42.5		179.2		123.3
Environmental Products		26.3		21.6		64.2		51.8
Building Materials		18.0		19.9		54.9		57.5
Basic Minerals		25.5		31.2		77.2		90.5
Performance Materials		219.5		188.8		621.3		539.0
Paper PCC		93.1		96.3		284.6		282.0
Specialty PCC		16.9		16.4		51.2		50.8
Ground Calcium Carbonate		23.0		22.3		70.7		67.1
Talc		13.3		12.7		40.3		41.0
Specialty Minerals		146.3		147.7		446.8		440.9
Refractory Products		66.7		56.6		195.7		169.4
Metallurgical Products		12.4		12.3		38.3		38.6
Refractories		79.1		68.9		234.0		208.0
Energy Services		19.2		19.0		58.0		55.6
Total	$	464.1	$	424.4	$	1,360.1	$	1,243.5