Business Segment Information (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Business segment
Net sales	$ 233.6	$ 239.7
Operating income (loss)	23.6	17.4
COVID-19 costs	1.1	0.0
Restructuring and other non-routine costs	1.4	0.0
Due diligence and transaction costs	1.0	0.0
Unallocated corporate costs
Business segment
Operating income (loss)	(7.4)	(5.8)
Restructuring and other non-routine costs	0.3
Due diligence and transaction costs	1.0
Technical Products \| Operating segments
Business segment
Net sales	142.2	140.0
Operating income (loss)	16.2	11.3
COVID-19 costs	0.6
Restructuring and other non-routine costs	0.2
Fine Paper and Packaging \| Operating segments
Business segment
Net sales	91.4	99.7
Operating income (loss)	14.8	$ 11.9
COVID-19 costs	0.5
Restructuring and other non-routine costs	$ 0.9

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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