CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) [Abstract]
Net income	$ 88.3	$ 126.3	$ 168.5
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(6.1)	(78.9)	(78.9)
Pension and postretirement plan adjustments	5.6	35.3	45.2
Unrealized gain (loss) on cash flow hedges	(3.3)	7.8	8.4
Total other comprehensive loss, net of tax	(3.8)	(35.8)	(25.3)
Total comprehensive income including non-controlling interests	84.5	90.5	143.2
Less: Net income attributable to non-controlling interests	4.2	4.1	4.1
Less: Foreign currency translation adjustments attributable to non-controlling interests	(0.9)	(2.9)	(0.1)
Comprehensive income attributable to non-controlling interests	3.3	1.2	4.0
Comprehensive income attributable to Minerals Technologies Inc.	$ 81.2	$ 89.3	$ 139.2