Acquisitions - FiberMark Acquisition Narrative (Details) - USD ($)		12 Months Ended
	Aug. 01, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Nov. 01, 2017
Business Acquisition [Line Items]
Document Period End Date		Dec. 31, 2017
Acquired goodwill		$ 85,300,000	$ 70,400,000	$ 72,200,000
Acquisition/integration/restructuring costs		1,300,000	7,000,000	6,500,000
FiberMark
Business Acquisition [Line Items]
Business acquisition, purchase price	$ 118,000,000
Goodwill expected to be deductible for income tax purpose					$ 0
Acquisition/integration/restructuring costs			4,300,000	5,300,000
Net sales of acquiree since acquisition				58,100,000
Income from operations before income taxes of acquiree since acquisition				1,500,000
Various uncertain tax positions balance	4,700,000
Purchase price for uncertain tax position for goodwill	3,700,000
Purchase price for uncertain tax position for current assets	1,000,000
Technical Products
Business Acquisition [Line Items]
Acquired goodwill		$ 78,700,000	$ 63,800,000	$ 65,600,000
Technical Products | FiberMark
Business Acquisition [Line Items]
Acquired goodwill	18,900,000
Fine Paper and Packaging | FiberMark
Business Acquisition [Line Items]
Acquired goodwill	6,200,000
Other | FiberMark
Business Acquisition [Line Items]
Acquired goodwill	$ 400,000