Earnings Per Share (EPS) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Oct. 02, 2016	Jul. 03, 2016	Apr. 03, 2016	Dec. 31, 2015	Sep. 27, 2015	Jun. 28, 2015	Mar. 29, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Amounts attributable to MTI [Abstract]
Income from continuing operations	$ 37.5	$ 42.5	$ 22.3	$ 34.8	$ 17.8	$ 30.3	$ 27.5	$ 36.0	$ 133.4	$ 107.9	$ 90.3
Income from discontinued operations					0.0	0.0	0.0	0.0	0.0	0.0	2.1
Net income attributable to Minerals Technologies Inc. (MTI)	$ 36.7	$ 41.6	$ 21.2	$ 33.9	$ 17.0	$ 29.2	$ 26.6	$ 35.1	$ 133.4	$ 107.9	$ 92.4
Weighted average shares outstanding (in shares)									34,900,000	34,700,000	34,500,000
Earnings per share attributable to MTI [Abstract]
Continuing operations (in dollars per share)	$ 1.05	$ 1.19	$ 0.61	$ 0.97	$ 0.49	$ 0.84	$ 0.77	$ 1.01	$ 3.82	$ 3.11	$ 2.62
Discontinued operations (in dollars per share)	0	0	0	0	0	0	0	0	0	0	0.06
Basic earnings per share attributable to MTI (in dollars per share)	$ 1.05	$ 1.19	$ 0.61	$ 0.97	$ 0.49	$ 0.84	$ 0.77	$ 1.01	$ 3.82	$ 3.11	$ 2.68
Amounts attributable to MTI [Abstract]
Income from continuing operations	$ 37.5	$ 42.5	$ 22.3	$ 34.8	$ 17.8	$ 30.3	$ 27.5	$ 36.0	$ 133.4	$ 107.9	$ 90.3
Income from discontinued operations, net of tax					0.0	0.0	0.0	0.0	0.0	0.0	2.1
Net income attributable to Minerals Technologies Inc. (MTI)	$ 36.7	$ 41.6	$ 21.2	$ 33.9	$ 17.0	$ 29.2	$ 26.6	$ 35.1	$ 133.4	$ 107.9	$ 92.4
Weighted average shares outstanding (in shares)									34,900,000	34,700,000	34,500,000
Dilutive effect of stock options and stock units (in shares)									300,000	300,000	300,000
Weighted average shares outstanding, adjusted (in shares)									35,200,000	35,000,000	34,800,000
Earnings per share attributable to MTI [Abstract]
Continuing operations (in dollars per share)	$ 1.04	$ 1.18	$ 0.60	$ 0.97	$ 0.48	$ 0.83	$ 0.76	$ 1.01	$ 3.79	$ 3.08	$ 2.59
Discontinued operations (in dollars per share)	0	0	0	0	0	0	0	0	0	0	0.06
Diluted earnings per share attributable to MTI (in dollars per share)	$ 1.04	$ 1.18	$ 0.60	$ 0.97	$ 0.48	$ 0.83	$ 0.76	$ 1.01	$ 3.79	$ 3.08	$ 2.65
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities not included in the weighted average commons shares outstanding calculation (in shares)									784	386,766	12,888