CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Apr. 04, 2021	Mar. 29, 2020
Statements of Income [Abstract]
Net sales	$ 452.6	$ 417.5
Cost of goods sold	340.8	310.7
Production margin	111.8	106.8
Marketing and administrative expenses	48.0	43.4
Research and development expenses	5.0	5.1
Litigation expenses	0.0	0.6
Income from operations	58.8	57.7
Interest expense, net	(9.9)	(9.3)
Other non-operating income, net	0.5	0.6
Total non-operating deductions, net	(9.4)	(8.7)
Income from operations before tax and equity in earnings	49.4	49.0
Provision for taxes on income	8.9	9.7
Equity in earnings of affiliates, net of tax	0.5	0.3
Consolidated net income	41.0	39.6
Less: Net income attributable to non-controlling interests	1.1	1.0
Net income attributable to Minerals Technologies Inc.	$ 39.9	$ 38.6
Basic:
Income from operations attributable to Minerals Technologies Inc. (in dollars per share)	$ 1.18	$ 1.12
Diluted:
Income from operations attributable to Minerals Technologies Inc. (in dollars per share)	1.17	1.12
Cash dividends declared per common share (in dollars per share)	$ 0.05	$ 0.05
Shares used in computation of earnings per share:
Basic (in shares)	33.8	34.4
Diluted (in shares)	34.0	34.4