Business Segment Information - Net Sales and Income from Operation by Business Segment (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Segment Reporting Information [Line Items]
Net sales	$ 81,089	$ 93,870	$ 155,229	$ 186,521
Income from Operations	2,581	9,255	14,712	10,605
Energy Solutions Segment [Member]
Segment Reporting Information [Line Items]
Net sales	51,136	52,499	91,109	106,208
Income from Operations	5,901	10,535	9,525	14,359
Industrial Solutions Segment [Member]
Segment Reporting Information [Line Items]
Net sales	18,324	22,796	36,121	46,099
Income from Operations	1,273	1,935	2,642	4,669
Fluid Handling Solutions Segment [Member]
Segment Reporting Information [Line Items]
Net sales	11,791	18,348	27,999	34,164
Income from Operations	2,182	4,148	5,392	7,457
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Net sales	(162)	227		50
Income from Operations	(6,539)	(6,935)	(2,025)	(14,782)
Inter-segment Elimination [Member]
Segment Reporting Information [Line Items]
Income from Operations	$ (236)	$ (428)	$ (822)	$ (1,098)