Segment Information - Schedule of Operating Segment Reporting Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Segment Reporting Information [Line Items]
Total sales	$ 609.9	$ 540.1
Operating income	102.8	82.4
Depreciation and amortization	38.7	29.8
Stock-based compensation	11.1	9.9
Accrual basis additions to capital expenditures	57.5	45.3
Corporate & Other and Intersegment Elimination
Segment Reporting Information [Line Items]
Total sales	(19.3)	(19.2)
Operating income	(24.5)	(18.5)
Stock-based compensation	6.2	5.6
Composite Materials
Segment Reporting Information [Line Items]
Total sales	487.7	444.6
Composite Materials | Intersegment Elimination
Segment Reporting Information [Line Items]
Total sales	19.2	19.2
Composite Materials | Operating Segments
Segment Reporting Information [Line Items]
Total sales	506.9	463.8
Operating income	112.5	91.0
Depreciation and amortization	34.9	27.5
Stock-based compensation	4.1	3.6
Accrual basis additions to capital expenditures	56.8	45.3
Engineered Products
Segment Reporting Information [Line Items]
Total sales	122.2	95.5
Engineered Products | Intersegment Elimination
Segment Reporting Information [Line Items]
Total sales	0.1
Engineered Products | Operating Segments
Segment Reporting Information [Line Items]
Total sales	122.3	95.5
Operating income	14.8	9.9
Depreciation and amortization	3.8	2.3
Stock-based compensation	0.8	$ 0.7
Accrual basis additions to capital expenditures	$ 0.7