CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 29, 2019	Sep. 30, 2018	Sep. 29, 2019	Sep. 30, 2018
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) [Abstract]
Consolidated net income	$ 39.1	$ 42.9	$ 106.7	$ 129.2
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(23.1)	(23.1)	(42.2)	(62.4)
Pension and postretirement plan adjustments	1.6	4.6	4.9	8.4
Unrealized gains (losses) on derivative instruments	4.5	(0.4)	2.5	(0.1)
Total other comprehensive loss, net of tax	(17.0)	(18.9)	(34.8)	(54.1)
Total comprehensive income including non-controlling interests	22.1	24.0	71.9	75.1
Comprehensive income attributable to non-controlling interests	(0.3)	(0.6)	(2.6)	(1.8)
Comprehensive income attributable to Minerals Technologies Inc.	$ 21.8	$ 23.4	$ 69.3	$ 73.3

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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