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Non-cash Impairment Loss, Restructuring, Integration And Pension Settlement Charges

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The amount of net gain (loss) recognized in net periodic benefit cost as a result of an event that significantly eliminates the expected years of future service of present employees or eliminates for a significant number of employees the accrual of defined benefits for some or all of their future services.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Business Segment and Geographic Information - Segment Information (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Business segment
Net sales									$ 1,034.9	$ 979.9	$ 941.5
Operating income (loss)	$ 17.8	$ 16.5	$ (4.3)	$ 24.1	$ 19.1	$ 29.0	$ 29.2	$ 27.0	54.1	104.3	114.1
Acquisition related adjustments	0.8	3.1							(3.9)	0.0	0.0
Insurance recoveries		0.4				3.2			0.4	3.2	0.0
Pension plan settlement charge			1.0		0.6				0.8	0.6
Depreciation and amortization									36.1	33.3	32.0
Capital expenditures									38.1	42.7	68.5
Total Assets	861.2				904.4				861.2	904.4
Long-Lived Assets	583.3				619.2				583.3	619.2
United States
Business segment
Long-Lived Assets	366.3				393.1				366.3	393.1
Germany
Business segment
Long-Lived Assets	157.9				164.6				157.9	164.6
Rest of Europe
Business segment
Long-Lived Assets	59.1				61.5				59.1	61.5
Unallocated corporate costs
Business segment
Operating income (loss)									(19.8)	(20.1)	(21.1)
Pre-operating costs related to conversion of fine paper machine to filtration											2.7
Depreciation and amortization									1.6	1.7	1.5
Capital expenditures									1.4	0.5	2.7
Total Assets	40.1				29.8				40.1	29.8
Unallocated corporate costs \| Supplemental Employee Retirement Plan
Business segment
Integration costs										1.3
Restructuring costs and pension settlement charges										1.9
Product
Business segment
Net sales	240.9	$ 256.2	$ 271.3	$ 266.5	244.0	$ 245.1	$ 248.7	$ 242.1	1,034.9	979.9	941.5
Product \| United States
Business segment
Net sales									744.4	748.9	727.6
Product \| Germany
Business segment
Net sales									216.5	210.3	201.2
Product \| Rest of Europe
Business segment
Net sales									74.0	20.7	12.7
Technical Products \| Operating Segments
Business segment
Operating income (loss)									50.9	55.3	65.6
Non-cash impairment loss, restructuring, integration and pension settlement charges									2.5
Acquisition related adjustments									3.9
Depreciation and amortization									23.7	19.4	18.1
Capital expenditures									28.0	28.6	57.9
Total Assets	586.4				613.0				586.4	613.0
Technical Products \| Product \| Operating Segments
Business segment
Net sales									$ 567.6	$ 502.1	$ 466.4
Technical Products \| Product Concentration Risk \| Sales Revenue
Business segment
Percentage of concentration risk									100.00%	100.00%	100.00%
Technical Products \| Product Concentration Risk \| Filtration \| Sales Revenue
Business segment
Percentage of concentration risk									41.00%	44.00%	42.00%
Technical Products \| Product Concentration Risk \| Backings \| Sales Revenue
Business segment
Percentage of concentration risk									28.00%	32.00%	31.00%
Technical Products \| Product Concentration Risk \| Specialty \| Sales Revenue
Business segment
Percentage of concentration risk									31.00%	24.00%	27.00%
Fine Paper and Packaging \| Operating Segments
Business segment
Operating income (loss)									$ 29.4	$ 69.5	$ 70.7
Non-cash impairment loss, restructuring costs, and pension settlement charges									24.6
Integration costs											1.8
Insurance recoveries									0.3	2.9
Depreciation and amortization									9.9	11.0	11.1
Capital expenditures									8.7	12.5	7.6
Total Assets	$ 234.7				$ 261.6				234.7	261.6
Fine Paper and Packaging \| Product \| Operating Segments
Business segment
Net sales									$ 445.8	$ 455.3	$ 452.1
Fine Paper and Packaging \| Product Concentration Risk \| Sales Revenue
Business segment
Percentage of concentration risk									100.00%	100.00%	100.00%
Fine Paper and Packaging \| Product Concentration Risk \| Graphic Imaging \| Sales Revenue
Business segment
Percentage of concentration risk									78.00%	80.00%	81.00%
Fine Paper and Packaging \| Product Concentration Risk \| Packaging \| Sales Revenue
Business segment
Percentage of concentration risk									18.00%	16.00%	14.00%
Fine Paper and Packaging \| Product Concentration Risk \| Filing/Office \| Sales Revenue
Business segment
Percentage of concentration risk									4.00%	4.00%	5.00%
Other \| Operating Segments
Business segment
Operating income (loss)									$ (6.4)	$ (0.4)	$ (1.1)
Integration costs											1.1
Insurance recoveries									0.1	0.3
Pension plan settlement charge									6.0		0.8
Depreciation and amortization									0.9	1.2	1.3
Capital expenditures									0.0	1.1	0.3
Other \| Product \| Operating Segments
Business segment
Net sales									$ 21.5	$ 22.5	$ 23.0