Business Segment Information (Details) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Business segment        
Net sales $ 245.1 $ 232.9 $ 735.9 $ 721.0
Operating income (loss) 29.0 26.9 85.2 92.2
Unallocated corporate costs        
Business segment        
Operating income (loss) (4.6) (4.6) (14.6) (14.5)
Technical Products | Operating segments        
Business segment        
Net sales 125.9 114.1 375.1 362.1
Operating income (loss) 15.6 14.1 44.1 53.4
Fine Paper and Packaging | Operating segments        
Business segment        
Net sales 113.3 112.9 343.3 340.4
Operating income (loss) 17.8 17.3 55.6 53.2
Other | Operating segments        
Business segment        
Net sales 5.9 5.9 17.5 18.5
Operating income (loss) $ 0.2 $ 0.1 $ 0.1 $ 0.1