Restructuring Costs - Reconciliation of Accrued Restructuring Costs (Detail) - USD ($)	3 Months Ended						9 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2022	Sep. 30, 2021
Restructuring Reserve [Roll Forward]
Beginning Balance	$ 600,000	$ 600,000	$ 500,000	$ 1,100,000	$ 1,700,000	$ 2,300,000	$ 500,000	$ 2,300,000
Restructuring expense incurred	3,900,000	500,000	400,000	700,000	800,000	900,000	4,800,000	2,400,000
Cash payments	(500,000)	(500,000)	(300,000)	(1,200,000)	(1,400,000)	(1,500,000)
Ending Balance	4,000,000.0	600,000	600,000	600,000	1,100,000	1,700,000	4,000,000.0	600,000
2017 Altra Plan [Member]
Restructuring Reserve [Roll Forward]
Beginning Balance				300,000	400,000	500,000		500,000
Restructuring expense incurred							0
Cash payments				(100,000)	(100,000)	(100,000)
Ending Balance				200,000	300,000	400,000		200,000
2019 Altra Plan [Member]
Restructuring Reserve [Roll Forward]
Beginning Balance	600,000	600,000	500,000	800,000	1,300,000	1,800,000	500,000	1,800,000
Restructuring expense incurred	3,900,000	500,000	400,000	700,000	800,000	900,000	4,800,000	2,400,000
Cash payments	(500,000)	(500,000)	(300,000)	(1,100,000)	(1,300,000)	(1,400,000)
Ending Balance	$ 4,000,000.0	$ 600,000	$ 600,000	$ 400,000	$ 800,000	$ 1,300,000	$ 4,000,000.0	$ 400,000