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The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets of discontinued operations.

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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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Pre-Operating Costs, Conversion Costs of Property, Plant, And Equipment

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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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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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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Amount of depreciation and amortization expense attributable to disposal group, including, but not limited to, discontinued operation.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

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The net result for the period of deducting operating expenses from operating revenues.

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The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

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Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

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Business Segment and Geographic Information (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Business segment
Net sales	$ 220.5	$ 232.9	$ 246.0	$ 242.1	$ 230.4	$ 231.6	$ 211.3	$ 214.4	$ 941.5	$ 887.7	$ 839.7
Operating income (loss)	21.9	$ 26.9	$ 33.9	$ 31.4	20.9	$ 24.4	$ 27.7	$ 28.4	114.1	101.4	86.6
Integration/restructuring costs									7.0	6.5	2.3
Pension plan settlement charge									0.8	0.0	3.5
Loss on early extinguishment of debt									0.0	0.0	0.2
Depreciation and amortization									32.0	31.5	30.0
Total Continuing Operations									32.0	28.8	26.1
Discontinued operations									0.0	2.7	3.9
Capital expenditures									68.5	48.1	27.9
Total Continuing Operations									68.5	47.5	27.2
Discontinued operations									0.0	0.6	0.7
Total Assets	765.6				751.4				765.6	751.4
Long-Lived Assets	529.3				504.8				529.3	504.8
United States
Business segment
Net sales									727.6	687.3	612.0
Total Assets	563.6				533.2				563.6	533.2
Long-Lived Assets	377.4				342.0				377.4	342.0
Canada
Business segment
Total Assets	0.1				0.1				0.1	0.1
Europe
Business segment
Net sales									213.9	200.4	227.7
Total Assets	201.9				218.1				201.9	218.1
Long-Lived Assets	151.9				162.8				151.9	162.8
Unallocated corporate costs
Business segment
Operating income (loss)									(21.1)	(18.0)	(20.2)
Pre-operating costs related to conversion of fine paper machine to filtration									2.7
Pension plan settlement charge									0.8	0.8	3.5
Loss on early extinguishment of debt											0.2
Restructuring cost											0.7
Technical Products
Business segment
Net sales									466.4	429.2	403.6
Depreciation and amortization									18.1	16.5	14.6
Capital expenditures									57.9	36.0	16.1
Total Assets	487.6				483.4				487.6	483.4
Technical Products \| Operating Segments
Business segment
Operating income (loss)									65.6	54.1	46.0
Integration/restructuring costs									$ 1.4	$ 1.7	$ 1.6
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									42.00%	45.00%	42.00%
Technical Products \| Product Concentration Risk \| Backings \| Sales Revenue
Business segment
Percentage of concentration risk									31.00%	30.00%	29.00%
Technical Products \| Product Concentration Risk \| Specialty \| Sales Revenue
Business segment
Percentage of concentration risk									27.00%	25.00%	29.00%
Fine Paper and Packaging
Business segment
Net sales									$ 452.1	$ 442.7	$ 436.1
Depreciation and amortization									11.1	9.8	8.6
Capital expenditures									7.6	10.3	10.0
Total Assets	248.9				261.9				248.9	261.9
Fine Paper and Packaging \| Operating Segments
Business segment
Operating income (loss)									70.7	67.3	$ 60.8
Integration/restructuring costs									$ 1.8	$ 1.5
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									81.00%	80.00%	91.00%
Fine Paper and Packaging \| Product Concentration Risk \| Packaging \| Sales Revenue
Business segment
Percentage of concentration risk									14.00%	15.00%	9.00%
Fine Paper and Packaging \| Product Concentration Risk \| Filing/Office \| Sales Revenue
Business segment
Percentage of concentration risk									5.00%	5.00%	0.00%
Other
Business segment
Net sales									$ 23.0	$ 15.8	$ 0.0
Integration/restructuring costs									1.1	2.4
Depreciation and amortization									1.3	0.6	0.0
Capital expenditures									0.3	0.4	0.0
Other \| Operating Segments
Business segment
Operating income (loss)									(1.1)	(2.0)	0.0
Corporate and Other
Business segment
Depreciation and amortization									1.5	1.9	2.9
Capital expenditures									2.7	0.8	$ 1.1
Total Assets	$ 29.1				$ 6.1				$ 29.1	$ 6.1