Goodwill and Other Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2022

Goodwill and Other Intangible Assets [Abstract]

Goodwill

The balance of goodwill by segment and the activity occurring in the past two fiscal years is as follows:

(millions of dollars)	Performance Materials			Specialty Minerals			Refractories			Consolidated
Balance at December 31, 2020	$	752.4		$	12.7		$	43.4		$	808.5
Change in goodwill relating to:
Normerica acquisition		104.5			—			—			104.5
Foreign exchange translation		(3.9	)		(0.1	)		(1.5	)		(5.5	)
Total Changes	$	100.6		$	(0.1	)	$	(1.5	)	$	99.0
Balance at December 31, 2021	$	853.0		$	12.6		$	41.9		$	907.5
Change in goodwill relating to:
Concept Pet acquisition		9.2			—			—			9.2
Foreign exchange translation		(0.5	)		(0.8	)		(0.6	)		(1.9	)
Total Changes	$	8.7		$	(0.8	)	$	(0.6	)	$	7.3
Balance at December 31, 2022	$	861.7		$	11.8		$	41.3		$	914.8

Acquired Intangible Assets Subject to Amortization

Acquired intangible assets subject to amortization as of December 31, 2022 and December 31, 2021 were as follows:

			December 31, 2022				December 31, 2021
	Weighted Average Useful Life (Years)		Gross Carrying Amount		Accumulated Amortization		Gross Carrying Amount		Accumulated Amortization
Tradenames		34	$	221.2	$	52.2	$	221.6	$	44.9
Technology		13		18.8		12.6		18.8		11.2
Patents and trademarks		19		6.4		6.4		6.4		6.4
Customer relationships		21		78.4		11.7		75.2		7.9
		29	$	324.8	$	82.9	$	322.0	$	70.4