Condensed Consolidated Statement of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 29, 2013	Jun. 30, 2014	Jun. 29, 2013
Statement of Comprehensive Income [Abstract]
Net Income	$ 12,818	$ 10,676	$ 24,181	$ 22,535
Other Comprehensive income (loss):
Foreign currency translation adjustment	958	202	904	(6,681)
Change in fair value of interest rate swap, net of tax	(125)	537	(120)	537
Other comprehensive income (loss)	833	739	784	(6,144)
Comprehensive income	13,651	11,415	24,965	16,391
Comprehensive (income) loss attributable to noncontrolling interest	(56)	13	(93)	34
Comprehensive income attributable to Altra Industrial Motion Corp.	$ 13,595	$ 11,428	$ 24,872	$ 16,425

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 and other comprehensive income, attributable to noncontrolling interests. 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, attributable to parent entity.

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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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