Amount of depreciation and amortization of continued operations.

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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 continuing operations.

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No definition available.

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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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No definition available.

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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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No definition available.

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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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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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No definition available.

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- Definition

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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-Publisher FASB
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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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-Name Accounting Standards Codification
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- Definition

The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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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-Publisher FASB
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The net result for the period of deducting operating expenses from operating revenues.

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No definition available.

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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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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Business Segment and Geographic Information - Segment Information (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Business segment
Net sales	$ 244.0	$ 245.1	$ 248.7	$ 242.1	$ 220.5	$ 232.9	$ 246.0	$ 242.1	$ 979.9	$ 941.5	$ 887.7
Operating income (loss)	19.1	29.0	$ 29.2	$ 27.0	21.9	$ 26.9	$ 33.9	$ 31.4	104.3	114.1	101.4
Acquisition/integration/restructuring costs									1.3	7.0	6.5
Insurance recoveries		3.2							3.2	0.0	0.0
Pension plan settlement charge	0.4	$ 0.2							0.6	0.8	0.0
Depreciation and amortization									33.3	32.0	31.5
Total Continuing Operations									33.3	32.0	28.8
Discontinued operations									0.0	0.0	2.7
Capital expenditures									42.7	68.5	48.1
Total Continuing Operations									42.7	68.5	47.5
Discontinued operations									0.0	0.0	0.6
Total Assets	904.4				765.6				904.4	765.6
Long-Lived Assets	619.2				529.3				619.2	529.3
United States
Business segment
Net sales									748.9	727.6	687.3
Long-Lived Assets	393.1				377.4				393.1	377.4
Europe
Business segment
Net sales									231.0	213.9	200.4
Long-Lived Assets	226.1				151.9				226.1	151.9
Unallocated corporate costs
Business segment
Operating income (loss)									(20.1)	(21.1)	(18.0)
Pre-operating costs related to conversion of fine paper machine to filtration										2.7
Pension plan settlement charge										0.8	0.8
Depreciation and amortization									1.7	1.5	1.9
Capital expenditures									0.5	2.7	0.8
Total Assets	29.8				29.1				29.8	29.1
Unallocated corporate costs \| Supplemental Employee Retirement Plan
Business segment
Acquisition/integration/restructuring costs									1.3
Technical Products \| Operating Segments
Business segment
Net sales									502.1	466.4	429.2
Operating income (loss)									55.3	65.6	54.1
Acquisition/integration/restructuring costs										1.4	1.7
Depreciation and amortization									19.4	18.1	16.5
Capital expenditures									28.6	57.9	$ 36.0
Total Assets	613.0				487.6				$ 613.0	$ 487.6
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									44.00%	42.00%	45.00%
Technical Products \| Product Concentration Risk \| Backings \| Sales Revenue
Business segment
Percentage of concentration risk									32.00%	31.00%	30.00%
Technical Products \| Product Concentration Risk \| Specialty \| Sales Revenue
Business segment
Percentage of concentration risk									24.00%	27.00%	25.00%
Fine Paper and Packaging \| Operating Segments
Business segment
Net sales									$ 455.3	$ 452.1	$ 442.7
Operating income (loss)									69.5	70.7	67.3
Acquisition/integration/restructuring costs										1.8	1.5
Insurance recoveries									2.9
Depreciation and amortization									11.0	11.1	9.8
Capital expenditures									12.5	7.6	$ 10.3
Total Assets	$ 261.6				$ 248.9				$ 261.6	$ 248.9
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									80.00%	81.00%	80.00%
Fine Paper and Packaging \| Product Concentration Risk \| Packaging \| Sales Revenue
Business segment
Percentage of concentration risk									16.00%	14.00%	15.00%
Fine Paper and Packaging \| Product Concentration Risk \| Filing/Office \| Sales Revenue
Business segment
Percentage of concentration risk									4.00%	5.00%	5.00%
Other \| Operating Segments
Business segment
Net sales									$ 22.5	$ 23.0	$ 15.8
Operating income (loss)									(0.4)	(1.1)	(2.0)
Acquisition/integration/restructuring costs										1.1	2.4
Insurance recoveries									0.3
Depreciation and amortization									1.2	1.3	0.6
Capital expenditures									$ 1.1	$ 0.3	$ 0.4