Business Segment, Geographic and Major Customer Information - Assets by Reportable Segments (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Assets	$ 359,177	$ 383,215
Held for sale	7,197	43,900
Operating Segments
Segment Reporting Information [Line Items]
Assets	351,980	339,315
Operating Segments | Energy Chemistry Technologies
Segment Reporting Information [Line Items]
Assets	195,963	184,328
Operating Segments | Consumer and Industrial Chemistry Technologies
Segment Reporting Information [Line Items]
Assets	117,037	98,105
Corporate and Other
Segment Reporting Information [Line Items]
Assets	$ 38,980	$ 56,882