Segment Information - Schedule of Operating Segment Reporting Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Segment Reporting Information [Line Items]
Total sales	$ 451.9	$ 412.3	$ 1,383.7	$ 1,251.4
Operating income	79.0	69.0	228.7	203.9
Other operating expense			6.0
Depreciation and amortization	17.8	14.7	52.6	42.8
Stock-based compensation expense	2.5	2.7	14.0	14.7
Accrual basis additions to capital expenditures	74.4	39.8	179.2	121.9
Operating Segments
Segment Reporting Information [Line Items]
Total sales	451.9	412.3	1,383.7	1,251.4
Composite Materials
Segment Reporting Information [Line Items]
Total sales	359.3	329.7	1,113.9	1,013.9
Operating income	74.4	68.7	230.1	207.8
Depreciation and amortization	16.4	13.4	48.3	39.1
Stock-based compensation expense	0.9	1.0	4.3	4.3
Accrual basis additions to capital expenditures	72.4	36.8	173.4	113.2
Composite Materials | Operating Segments
Segment Reporting Information [Line Items]
Total sales	342.9	312.6	1,060.8	962.1
Composite Materials | Intersegment Elimination
Segment Reporting Information [Line Items]
Total sales	16.4	17.1	53.1	51.8
Engineered Products
Segment Reporting Information [Line Items]
Total sales	109.4	99.8	323.9	290.5
Operating income	16.7	14.9	50.7	43.4
Depreciation and amortization	1.3	1.2	4.1	3.5
Stock-based compensation expense	0.2	0.2	0.9	0.9
Accrual basis additions to capital expenditures	2.0	3.0	5.8	8.7
Engineered Products | Operating Segments
Segment Reporting Information [Line Items]
Total sales	109.0	99.7	322.9	289.3
Engineered Products | Intersegment Elimination
Segment Reporting Information [Line Items]
Total sales	0.4	0.1	1.0	1.2
Corporate and Other
Segment Reporting Information [Line Items]
Total sales	(16.8)	(17.2)	(54.1)	(53.0)
Operating income	(12.1)	(14.6)	(52.1)	(47.3)
Other operating expense			6.0
Depreciation and amortization	0.1	0.1	0.2	0.2
Stock-based compensation expense	1.4	1.5	8.8	9.5
Corporate and Other | Intersegment Elimination
Segment Reporting Information [Line Items]
Total sales	$ (16.8)	$ (17.2)	$ (54.1)	$ (53.0)