Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Apr. 02, 2023	Apr. 03, 2022
Earnings Per Share [Abstract]
Net income attributable to Minerals Technologies Inc.	$ 37.0	$ 44.1
Weighted average shares outstanding (in shares)	32,500,000	33,100,000
Dilutive effect of stock options and deferred restricted stock units (in shares)	0	100,000
Weighted average shares outstanding, adjusted (in shares)	32,500,000	33,200,000
Basic earnings per share attributable to Minerals Technologies Inc. (in dollars per share)	$ 1.14	$ 1.33
Diluted earnings per share attributable to Minerals Technologies Inc. (in dollars per share)	$ 1.14	$ 1.33
Stock Options [Member]
Earnings per Share [Abstract]
Options outstanding (in shares)	1,608,613	1,536,887
Anti-dilutive securities not included in computation of diluted earnings per share (in shares)	1,002,344	732,874