CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]
Consolidated net income	$ 95.5us-gaap_ProfitLoss	$ 83.4us-gaap_ProfitLoss	$ 76.2us-gaap_ProfitLoss
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(51.5)	(16.5)	1.5
Pension and postretirement plan adjustments	(31.1)	34.3	(7.7)
Unrealized gains (losses) on cash flow hedges	0	0.5	(0.2)
Total other comprehensive income (loss), net of tax	(82.6)	18.3	(6.4)
Total comprehensive income including non-controlling interests	12.9	101.7	69.8
Less: Net income (loss) attributable to non-controlling interests	3.1	3.1	2.1
Less: Foreign currency translation adjustments attributable to non-controlling interest	(1.0)	(1.7)	(0.6)
Comprehensive income (loss) attributable to non-controlling interest	2.1	1.4	1.5
Comprehensive income attributable to MTI	$ 10.8us-gaap_ComprehensiveIncomeNetOfTax	$ 100.3us-gaap_ComprehensiveIncomeNetOfTax	$ 68.3us-gaap_ComprehensiveIncomeNetOfTax

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 of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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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, attributable to noncontrolling interests.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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