Condensed Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Statement [Abstract]
Net sales	$ 609.0	$ 547.5	$ 1,218.9	$ 1,087.6
Cost of sales	440.2	402.7	882.9	800.2
Gross margin	168.8	144.8	336.0	287.4
Selling, general and administrative expenses	39.5	35.3	89.0	81.7
Research and technology expenses	14.2	13.0	29.1	26.8
Operating income	115.1	96.5	217.9	178.9
Interest expense, net	11.9	8.7	23.9	16.7
Income before income taxes, and equity in earnings from affiliated companies	103.2	87.8	194.0	162.2
Provision for income taxes	23.6	20.0	44.2	34.1
Income before equity in earnings from affiliated companies	79.6	67.8	149.8	128.1
Equity in earnings from affiliated companies	1.3	1.0	3.3	2.3
Net income	$ 80.9	$ 68.8	$ 153.1	$ 130.4
Basic net income per common share	$ 0.95	$ 0.77	$ 1.80	$ 1.45
Diluted net income per common share	0.94	0.76	1.78	1.44
Dividends per share	$ 0.15	$ 0.125	$ 0.30	$ 0.25
Weighted-average common shares:
Basic	85.2	88.8	85.1	89.4
Diluted	86.2	89.9	86.1	90.5