Business Segment Information - Intra-Segment and Inter-Segment Revenues (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Net sales	$ 316,011	$ 341,869	$ 337,339
Energy Solutions Segment [Member]
Segment Reporting Information [Line Items]
Net sales	205,494	210,319	211,185
Industrial Solutions Segment [Member]
Segment Reporting Information [Line Items]
Net sales	74,697	91,347	80,699
Fluid Handling Solutions Segment [Member]
Segment Reporting Information [Line Items]
Net sales	35,820	40,203	45,455
Intra - Segment Sales [Member]
Segment Reporting Information [Line Items]
Net sales	(24,984)	(16,228)	(12,479)
Intra - Segment Sales [Member] | Energy Solutions Segment [Member]
Segment Reporting Information [Line Items]
Net sales	(11,333)	(6,650)	(7,912)
Intra - Segment Sales [Member] | Industrial Solutions Segment [Member]
Segment Reporting Information [Line Items]
Net sales	(12,749)	(8,278)	(3,084)
Intra - Segment Sales [Member] | Fluid Handling Solutions Segment [Member]
Segment Reporting Information [Line Items]
Net sales	(902)	(1,300)	(1,483)
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales	343,745	360,445	352,319
Operating Segments [Member] | Energy Solutions Segment [Member]
Segment Reporting Information [Line Items]
Net sales	218,290	217,359	220,334
Operating Segments [Member] | Industrial Solutions Segment [Member]
Segment Reporting Information [Line Items]
Net sales	88,694	101,369	84,424
Operating Segments [Member] | Fluid Handling Solutions Segment [Member]
Segment Reporting Information [Line Items]
Net sales	36,761	41,717	47,561
Inter-segment Elimination [Member] | Industrial Inter-Segment Sales [Member]
Segment Reporting Information [Line Items]
Net sales	(764)	(604)	(1,848)
Inter-segment Elimination [Member] | Energy Inter-Segment Sales [Member]
Segment Reporting Information [Line Items]
Net sales	(1,232)	(1,677)	(607)
Inter-segment Elimination [Member] | Fluid Handling Filtration Inter-Segment Sales [Member]
Segment Reporting Information [Line Items]
Net sales	(754)	(67)	(46)
Inter-segment Elimination [Member] | Energy Solutions Segment [Member] | Industrial Inter-Segment Sales [Member]
Segment Reporting Information [Line Items]
Net sales	(725)	(390)	(1,232)
Inter-segment Elimination [Member] | Energy Solutions Segment [Member] | Fluid Handling Filtration Inter-Segment Sales [Member]
Segment Reporting Information [Line Items]
Net sales	(738)		(5)
Inter-segment Elimination [Member] | Industrial Solutions Segment [Member] | Energy Inter-Segment Sales [Member]
Segment Reporting Information [Line Items]
Net sales	(1,232)	(1,677)	(600)
Inter-segment Elimination [Member] | Industrial Solutions Segment [Member] | Fluid Handling Filtration Inter-Segment Sales [Member]
Segment Reporting Information [Line Items]
Net sales	(16)	(67)	(41)
Inter-segment Elimination [Member] | Fluid Handling Solutions Segment [Member] | Industrial Inter-Segment Sales [Member]
Segment Reporting Information [Line Items]
Net sales	$ (39)	$ (214)	(616)
Inter-segment Elimination [Member] | Fluid Handling Solutions Segment [Member] | Energy Inter-Segment Sales [Member]
Segment Reporting Information [Line Items]
Net sales			$ (7)