Business Segment, Geographic and Major Customer Information - Reportable Segments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Summarized financial information regarding reportable segments
Net revenue from external customers	$ 85,177	$ 64,079	$ 165,131	$ 127,890
Gross profit	26,091	21,718	53,833	45,511
Income (loss) from operations	(1,252)	156	(1,874)	524
Depreciation and amortization	2,991	2,402	6,023	4,651
Capital expenditures	2,631	4,448	4,508	8,238
Operating Segments | Energy Chemistry Technologies
Summarized financial information regarding reportable segments
Net revenue from external customers	65,875	43,385	126,640	88,064
Gross profit	22,804	17,660	45,106	36,429
Income (loss) from operations	9,299	7,584	17,848	15,597
Depreciation and amortization	1,795	1,237	3,644	2,480
Capital expenditures	1,956	3,685	2,470	6,699
Operating Segments | Consumer and Industrial Chemistry Technologies
Summarized financial information regarding reportable segments
Net revenue from external customers	19,302	20,694	38,491	39,826
Gross profit	3,287	4,058	8,727	9,082
Income (loss) from operations	1,216	2,686	4,921	6,075
Depreciation and amortization	583	608	1,162	1,118
Capital expenditures	397	204	897	346
Corporate and Other
Summarized financial information regarding reportable segments
Net revenue from external customers	0	0	0	0
Gross profit	0	0	0	0
Income (loss) from operations	(11,767)	(10,114)	(24,643)	(21,148)
Depreciation and amortization	613	557	1,217	1,053
Capital expenditures	$ 278	$ 559	$ 1,141	$ 1,193