Acquisition of the New Business - Pro Forma Adjustments (Details) - USD ($) $ in Thousands		3 Months Ended	12 Months Ended
	Nov. 02, 2016	Dec. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Pro forma results of operations
Amount borrowed			$ 328,249	$ 111,400	$ 97,200
First Amended and Restated Credit Agreement | Revolving credit facility
Pro forma results of operations
Amount borrowed	$ 160,000	$ 160,000
Activated Carbon and Filter Aid Business (New Business)
Pro forma results of operations
Net income			29,326	33,119
Activated Carbon and Filter Aid Business (New Business) | Incremental deprecation and amortization associated with fair value adjustments to property, plant and equipment and intangible assets
Pro forma results of operations
Net income			(3,200)	(3,200)
Activated Carbon and Filter Aid Business (New Business) | Incremental interest expense
Pro forma results of operations
Net income			(3,300)	(3,900)
Activated Carbon and Filter Aid Business (New Business) | Step-up of inventory
Pro forma results of operations
Net income			1,500	(2,100)
Activated Carbon and Filter Aid Business (New Business) | Acquisition-related transaction expenses
Pro forma results of operations
Net income			$ 14,000	$ (14,000)