CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions	3 Months Ended
	Mar. 30, 2025	Mar. 31, 2024
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) [Abstract]
Net income (loss)	$ (143.0)	$ 47.6
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	9.9	(24.3)
Pension and postretirement plan adjustments	0.1	0.2
Unrealized (loss) gains on cash flow hedges	(0.3)	1.4
Total other comprehensive income (loss), net of tax	9.7	(22.7)
Total comprehensive income (loss) including non-controlling interests	(133.3)	24.9
Comprehensive income attributable to non-controlling interests	0.4	0.2
Comprehensive income (loss) attributable to Minerals Technologies Inc.	$ (133.7)	$ 24.7