Organization and Nature of Operations	3 Months Ended
Mar. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Organization and Nature of Operations	1. Organization and Nature of Operations Headquartered in Braintree, Massachusetts, Altra Industrial Motion Corp. (the “Company,” “Altra,” “we,” or “our”) is a leading global designer, producer and marketer of a wide range of electro-mechanical power transmission and motion control products. The Company brings together strong brands with production facilities in seventeen countries. Altra’s leading brands include Ameridrives Couplings, Bauer Gear Motor, Bibby Turboflex, Boston Gear, Delroyd Worm Gear, Formsprag Clutch, Guardian Couplings, Huco, Industrial Clutch, Inertia Dynamics, Jacobs Vehicle Systems, Kilian Manufacturing, Kollmorgen, Lamiflex Couplings, Marland Clutch, Matrix, Nuttall Gear, Portescap, Stieber Clutch, Stromag, Svendborg Brakes, TB Wood’s, Thomson, Twiflex, Warner Electric, Warner Linear, and Wichita Clutch.

The entire disclosure for the nature of an entity's business, major products or services, principal markets including location, and the relative importance of its operations in each business and the basis for the determination, including but not limited to, assets, revenues, or earnings. For an entity that has not commenced principal operations, disclosures about the risks and uncertainties related to the activities in which the entity is currently engaged and an understanding of what those activities are being directed toward.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e5967-108592

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-URI http://asc.fasb.org/topic&trid=2134479

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