Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 197.8		$ 197.8
Accumulated Amortization	22.8		19.5
Net Carrying Amount	175.0		178.3
Amortization expense of intangible assets	3.1	$ 1.1
Estimated Amortization Expense
Estimated average amortization expense in each of next five years	11.7
Trade names [Member] \| Advanced Materials & Structures Segment [Member]
Indefinite-lived Intangible Assets [Line Items]
Unamortized intangible assets	35.6		35.6
Customer-Related Intangibles [Member] \| Engineered Papers Segment [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	10.0		10.0
Accumulated Amortization	10.0		10.0
Net Carrying Amount	0.0		0.0
Customer relationships [Member] \| Advanced Materials & Structures Segment [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	167.7		167.7
Accumulated Amortization	9.1		6.4
Net Carrying Amount	158.6		161.3
Developed Technology Rights [Member] \| Advanced Materials & Structures Segment [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	16.0		16.0
Accumulated Amortization	2.8		2.4
Net Carrying Amount	13.2		13.6
Customer Contracts [Member] \| Advanced Materials & Structures Segment [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	0.9		0.9
Accumulated Amortization	0.6		0.5
Net Carrying Amount	0.3		0.4
Non-Compete Agreements [Member] \| Advanced Materials & Structures Segment [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1.7		1.7
Accumulated Amortization	0.2		0.1
Net Carrying Amount	1.5		1.6
Patents [Member] \| Advanced Materials & Structures Segment [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1.5		1.5
Accumulated Amortization	0.1		0.1
Net Carrying Amount	$ 1.4		$ 1.4

Finite-Lived Intangible Assets, Amortization Expense, Estimated Average Expense for Each of the Next Five Years

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
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- References

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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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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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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+ References

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- Definition

Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)
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