Segment Information - Goodwill (Details) - USD ($) $ in Thousands	9 Months Ended	11 Months Ended
	Sep. 30, 2017	Sep. 30, 2017	Dec. 31, 2016	Nov. 02, 2016
Segment Information
Goodwill	$ 76,058	$ 76,058	$ 66,316
Activated Carbon and Filter Aid Business (New Business)
Segment Information
Goodwill	47,057	47,057		$ 42,844
Goodwill adjustments
Acquisition post closing adjustments		4,213
Activated Carbon
Segment Information
Goodwill	44,500	44,500
Activated Carbon | Activated Carbon and Filter Aid Business (New Business)
Segment Information
Goodwill	29,000	29,000
Goodwill adjustments
Acquisition post closing adjustments	2,500
Alternative Materials
Segment Information
Goodwill	19,500	19,500
Alternative Materials | Activated Carbon and Filter Aid Business (New Business)
Segment Information
Goodwill	18,100	18,100
Goodwill adjustments
Acquisition post closing adjustments	1,700
Advanced Water Purification
Segment Information
Goodwill	$ 12,100	$ 12,100