Business Segment Information - Property and Equipment Additions, Depreciation and Amortization and Identifiable Assets (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Segment Reporting Information [Line Items]
Property and equipment additions	$ 126	$ 231	$ 591	$ 641
Depreciation and amortization	3,459	4,030	6,956	8,168
Identifiable Assets	421,401		421,401		$ 438,549
Energy Solutions Segment [Member]
Segment Reporting Information [Line Items]
Property and equipment additions	15	116	32	352
Depreciation and amortization	2,190	2,417	4,348	4,935
Identifiable Assets	278,901		278,901		258,218
Industrial Solutions Segment [Member]
Segment Reporting Information [Line Items]
Property and equipment additions	90	31	165	40
Depreciation and amortization	205	391	487	782
Identifiable Assets	56,352		56,352		66,723
Fluid Handling Solutions Segment [Member]
Segment Reporting Information [Line Items]
Property and equipment additions	11	70	284	219
Depreciation and amortization	1,002	1,197	1,996	2,395
Identifiable Assets	75,703		75,703		100,917
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Property and equipment additions	10	14	110	30
Depreciation and amortization	62	$ 25	125	$ 56
Identifiable Assets	$ 10,445		$ 10,445		$ 12,691