Statements of Consolidated Income (Unaudited) - USD ($) shares in Thousands, $ in Millions		3 Months Ended
		Mar. 31, 2018	Mar. 31, 2017
Income Statement [Abstract]
Net sales		$ 388.0	$ 355.3
Cost of products sold:
Cost of products sold, excluding depreciation and amortization and other items1	[1]	316.7	262.7
Depreciation and amortization		10.5	9.6
Selling, general, administrative, research and development2	[2]	23.6	23.7
Other operating charges, net		0.1	0.0
Total costs and expenses		350.9	296.0
Operating income		37.1	59.3
Other (expense) income:
Interest expense		(5.6)	(5.6)
Other income, net		0.1	0.8
Income before income taxes		31.6	54.5
Income tax provision		(5.9)	(18.5)
Net income		$ 25.7	$ 36.0
Net income per common share:
Basic (in dollars per share)		$ 1.54	$ 2.07
Diluted (in dollars per share)		$ 1.51	$ 2.04
Weighted-average number of common shares outstanding (in thousands):
Basic (shares)		16,707	17,385
Diluted (shares)		17,031	17,603
Cash dividends declared (in dollars per share)		$ 0.55	$ 0.50

[1] See Note 4 for discussion of our adoption of ASU 2017-12 (as defined in Note 1) and the related reclassification of amounts previously presented in the Statements of Consolidated Income within Unrealized (gain) loss on derivative instruments and now included within Cost of products sold, excluding depreciation and amortization and other items.

[2] See Note 1 for discussion of our adoption of ASU 2017-07 (as defined in Note 1) and the related reclassification of amounts previously presented in the Statements of Consolidated Income within Selling, general, administrative, research and development and now included within Other (expense) income.