Segment Information - Schedule of Operating Segment Reporting Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Segment Reporting Information [Line Items]
Total sales	$ 471.8us-gaap_SalesRevenueGoodsNet	$ 461.7us-gaap_SalesRevenueGoodsNet
Operating income	82.6us-gaap_OperatingIncomeLoss	74.6us-gaap_OperatingIncomeLoss
Depreciation and amortization	18.3	17.1
Stock-based compensation expense	12.0us-gaap_ShareBasedCompensation	8.8us-gaap_ShareBasedCompensation
Accrual basis additions to capital expenditures	66.5	40.0
Operating Segments
Segment Reporting Information [Line Items]
Total sales	471.8	461.7
Composite Materials
Segment Reporting Information [Line Items]
Total sales	387.8	374.8
Operating income	89.2	75.9
Depreciation and amortization	16.7	15.6
Stock-based compensation expense	3.6	3.3
Accrual basis additions to capital expenditures	62.1	38.4
Composite Materials \| Operating Segments
Segment Reporting Information [Line Items]
Total sales	367.4	356.3
Composite Materials \| Intersegment Elimination
Segment Reporting Information [Line Items]
Total sales	20.4	18.5
Engineered Products
Segment Reporting Information [Line Items]
Total sales	104.5	105.5
Operating income	14.7	16.4
Depreciation and amortization	1.5	1.4
Stock-based compensation expense	0.5	0.7
Accrual basis additions to capital expenditures	4.4	1.6
Engineered Products \| Operating Segments
Segment Reporting Information [Line Items]
Total sales	104.4	105.4
Engineered Products \| Intersegment Elimination
Segment Reporting Information [Line Items]
Total sales	0.1	0.1
Corporate and Other
Segment Reporting Information [Line Items]
Total sales	(20.5)	(18.6)
Operating income	(21.3)	(17.7)
Depreciation and amortization	0.1	0.1
Stock-based compensation expense	7.9	4.8
Corporate and Other \| Intersegment Elimination
Segment Reporting Information [Line Items]
Total sales	$ (20.5)	$ (18.6)

Future cash outflow to pay for purchases of fixed assets that have occurred.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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