Business Segment Information - Net Sales and Income from Operation by Business Segment (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting Information [Line Items]
Net sales	$ 81,179	$ 81,089	$ 167,190	$ 155,229
Income from operations	2,018	2,581	6,907	14,712
Energy Solutions Segment [Member]
Segment Reporting Information [Line Items]
Net sales	50,572	51,136	105,760	91,109
Income from operations	6,351	5,901	15,642	9,525
Industrial Solutions Segment [Member]
Segment Reporting Information [Line Items]
Net sales	20,083	19,517	38,936	37,965
Income from operations	515	1,480	1,117	2,678
Fluid Handling Solutions Segment [Member]
Segment Reporting Information [Line Items]
Net sales	10,524	10,598	22,494	26,155
Income from operations	1,481	1,975	3,839	5,356
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Net sales		(162)
Income from operations	$ (6,329)	(6,539)	$ (13,691)	(2,025)
Inter-segment Elimination [Member]
Segment Reporting Information [Line Items]
Income from operations		$ (236)		$ (822)