Segment Information - Expenditures for Long-Lived Assets and Total Assets (Details 2) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Information
Expenditures for Long-Lived Assets	$ 62,228	$ 63,912	$ 29,557
Assets	656,518	621,661	590,078
Accounts payable and accrued liabilities
Segment Information
Property, plant and equipment expenditures	2,100	2,200	500
Activated Carbon and Service
Segment Information
Expenditures for Long-Lived Assets	57,559	60,470	25,885
Assets	597,274	564,734	527,430
Equipment
Segment Information
Expenditures for Long-Lived Assets	4,266	2,947	3,325
Assets	52,894	50,610	55,558
Consumer
Segment Information
Expenditures for Long-Lived Assets	403	495	347
Assets	$ 6,350	$ 6,317	$ 7,090