Quarterly Financial Data (unaudited) (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
Revenue from External Customer [Line Items]
Net sales	$ 401.3	$ 399.5	$ 427.0	$ 410.2	$ 429.9	$ 451.0	$ 463.4	$ 453.3	$ 1,638.0	$ 1,797.6	$ 1,725.0
Gross profit	111.4	115.2	121.1	112.7	109.3	118.9	126.2	116.6	460.4	471.0	435.4
Income from operations	56.5	67.3	39.5	57.6	37.7	49.9	52.8	59.9	220.9	200.3	168.8
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
Basic earnings per share attributable to MTI shareholders [Abstract]
Income from 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
Income from discontinued operations (in dollars per share)	0	0	0	0	0	0	0	0	0	0	0.06
Net income (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
Diluted earnings per share attributable to MTI shareholders [Abstract]
Income from 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
Loss from discontinued operations (in dollars per share)	0	0	0	0	0	0	0	0	0	0	0.06
Net income (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
Market price range per share of common stock [Abstract]
High (in dollars per share)	82.90	72.51	61.66	57.12	61.80	68.15	74.21	74.74
Low (in dollars per share)	66.10	56.00	52.53	37.03	45.35	46.69	66.49	59.00
Close (in dollars per share)	77.25	70.69	57.38	57.12	45.86	50.31	69.02	70.65	77.25	$ 45.86
Dividends paid per common share (in dollars per share)	$ 0.05	$ 0.05	$ 0.05	$ 0.05	$ 0.05	$ 0.05	$ 0.05	$ 0.05	$ 0.20
Specialty Minerals [Member]
Revenue from External Customer [Line Items]
Net sales	$ 138.0	$ 147.3	$ 150.6	$ 155.6	$ 157.6	$ 156.5	$ 156.5	$ 154.0
Refractories [Member]
Revenue from External Customer [Line Items]
Net sales	68.0	63.4	73.9	69.2	68.2	77.4	76.4	73.9
Performance Materials [Member]
Revenue from External Customer [Line Items]
Net sales	135.7	119.5	128.6	119.0	131.3	126.5	129.1	127.9
Construction Technologies [Member]
Revenue from External Customer [Line Items]
Net sales	39.3	49.5	53.9	40.6	39.4	49.7	52.1	38.9
Energy Services [Member]
Revenue from External Customer [Line Items]
Net sales	$ 20.3	$ 19.8	$ 20.0	$ 25.8	$ 33.4	$ 40.9	$ 49.3	$ 58.6