Earnings (Loss) per Share (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 30, 2025	Mar. 31, 2024
Earnings (Loss) per Share [Abstract]
Net income (loss) attributable to Minerals Technologies Inc.	$ (144.0)	$ 46.7
Weighted average shares outstanding (in shares)	31,900,000	32,300,000
Dilutive effect of stock options and deferred restricted stock units (in shares)	0	100,000
Weighted average shares outstanding, adjusted (in shares)	31,900,000	32,400,000
Basic earnings (loss) per share attributable to Minerals Technologies Inc. (in dollars per share)	$ (4.51)	$ 1.45
Diluted earnings (loss) per share attributable to Minerals Technologies Inc. (in dollars per share)	$ (4.51)	$ 1.44
Stock Options [Member]
Earnings (Loss) per Share [Abstract]
Options outstanding (in shares)	1,596,748	1,671,687
Anti-dilutive securities not included in computation of diluted earnings per share (in shares)	1,596,748	900,163