CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jul. 02, 2023	Jun. 30, 2024	Jul. 02, 2023
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]
Net income	$ 20.9	$ 27.6	$ 68.5	$ 65.7
Other comprehensive loss, net of tax:
Foreign currency translation adjustments	(9.9)	(26.1)	(34.3)	(16.0)
Pension and postretirement plan adjustments	0.2	0.4	0.5	0.9
Unrealized gains (losses) on derivative instruments	0.1	0.5	1.5	(1.9)
Total other comprehensive loss, net of tax	(9.6)	(25.2)	(32.3)	(17.0)
Total comprehensive income including non-controlling interests	11.3	2.4	36.2	48.7
Comprehensive income (loss) attributable to non-controlling interests	0.4	0.1	0.6	(1.3)
Comprehensive income attributable to Minerals Technologies Inc.	$ 10.9	$ 2.3	$ 35.6	$ 50.0