Business Segment Information - Net Sales and Income from Operation by Business Segment (Detail) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting Information [Line Items]
Net sales		$ 78,680	$ 75,170	$ 150,572	$ 155,656
Income from operations		2,145	4,395	5,199	8,633
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Income from operations	[1]	(7,930)	(6,087)	(14,868)	(13,502)
Engineered Systems Segment [Member]
Segment Reporting Information [Line Items]
Net sales		43,360	49,074	85,417	99,720
Income from operations		5,634	8,646	11,804	17,203
Industrial Process Solutions Segment [Member]
Segment Reporting Information [Line Items]
Net sales		35,320	26,096	65,155	55,936
Income from operations		$ 4,441	$ 1,836	$ 8,263	$ 4,932

[1] Includes corporate compensation, professional services, information technology, and other general and administrative corporate expenses