Business Segment, Geographic and Major Customer Information (Assets by Reportable Segments) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Assets	$ 386,588	$ 403,090
Held for sale	43,900	115,972
Operating Segments
Segment Reporting Information [Line Items]
Assets	342,688	287,118
Operating Segments | Energy Chemistry Technologies
Segment Reporting Information [Line Items]
Assets	184,328	153,447
Operating Segments | Consumer and Industrial Chemistry Technologies
Segment Reporting Information [Line Items]
Assets	98,105	93,038
Corporate and Other
Segment Reporting Information [Line Items]
Assets	$ 60,255	$ 40,633