Statements of Consolidated Income (Unaudited) - USD ($) shares in Thousands, $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Statement [Abstract]
Net sales	$ 375.3		$ 415.4		$ 770.5	$ 803.4
Costs and expenses:
Cost of products sold, excluding depreciation and amortization and other items	303.5		343.4		618.6	660.1
Depreciation and amortization	12.1		10.9		24.0	21.4
Selling, general, administrative, research and development	27.2		26.4		52.4	50.0
Other operating charges, net	0.1		0.0		0.1	0.1
Total costs and expenses	342.9		380.7		695.1	731.6
Operating income	32.4		34.7		75.4	71.8
Other (expense) income:
Interest expense	(5.8)		(5.7)		(11.5)	(11.3)
Other (expense) income, net	(0.1)		(0.5)		0.4	(0.4)
Income before income taxes	26.5		28.5		64.3	60.1
Income tax provision	(7.3)		(7.8)		(17.1)	(13.7)
Net income	$ 19.2	$ 28.0	$ 20.7	$ 25.7	$ 47.2	$ 46.4
Net income per common share:
Basic (in dollars per share)	$ 1.19		$ 1.24		$ 2.93	$ 2.78
Diluted (in dollars per share)	$ 1.18		$ 1.22		$ 2.89	$ 2.74
Weighted-average number of common shares outstanding:
Basic (shares)	16,063		16,685		16,085	16,696
Diluted (shares)	16,240		16,905		16,298	16,962