Segment Information (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) segment	Jun. 30, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments \| segment			2
Number of reportable segments \| segment			2
Net Sales [Abstract]
Net sales	$ 255.3	$ 217.3	$ 488.6	$ 431.9
Percentage of Net Sales (in hundredths)	100.00%	100.00%	100.00%	100.00%
Operating Profit [Abstract]
Operating Profit	$ 39.5	$ 37.5	$ 66.1	$ 69.1
Operating Profit (in hundredths)	100.00%	100.00%	100.00%	100.00%
Operating Segments [Member] \| Engineered Papers [Member]
Net Sales [Abstract]
Net sales	$ 137.5	$ 145.3	$ 270.8	$ 288.9
Percentage of Net Sales (in hundredths)	53.90%	66.90%	55.40%	66.90%
Operating Profit [Abstract]
Operating Profit	$ 30.8	$ 35.9	$ 57.7	$ 71.4
Operating Profit (in hundredths)	78.00%	95.70%	87.30%	103.30%
Operating Segments [Member] \| Advanced Materials & Structures [Member]
Net Sales [Abstract]
Net sales	$ 117.8	$ 72.0	$ 217.8	$ 143.0
Percentage of Net Sales (in hundredths)	46.10%	33.10%	44.60%	33.10%
Operating Profit [Abstract]
Operating Profit	$ 16.6	$ 8.9	$ 25.5	$ 14.1
Operating Profit (in hundredths)	42.00%	23.70%	38.60%	20.40%
Unallocated [Member]
Operating Profit [Abstract]
Operating Profit	$ (7.9)	$ (7.3)	$ (17.1)	$ (16.4)
Operating Profit (in hundredths)	(20.00%)	(19.40%)	(25.90%)	(23.70%)

The percentage of segment operating profit contribution to total operating profit.

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The percentage of net product revenue to total net revenue from the sale of goods.

+ References

No definition available.

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- Definition

Segment Net Sales [Abstract]

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Segment Operating Profit [Abstract]

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

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- Definition

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

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(a))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

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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