Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019		Dec. 31, 2018		Dec. 31, 2017
Quarterly Financial Data [Abstract]
Net sales	$ 368.7	$ 374.9	$ 375.3	$ 395.2	$ 389.4	$ 393.1	$ 415.4	$ 388.0	$ 1,514.1		$ 1,585.9		$ 1,397.5
Cost of products sold, excluding depreciation and amortization and other items	298.0	298.6	303.5	315.1	317.3	323.3	343.4	316.7	1,215.2	[1]	1,300.7	[1]	1,085.9	[1]
Gross Profit	70.7	76.3	71.8	80.1	72.1	69.8	72.0	71.3
Operating income	9.6	40.7	32.4	43.0	36.9	34.9	34.7	37.1	125.7		143.6		155.2
Net income (loss)	$ (10.6)	$ 25.4	$ 19.2	$ 28.0	$ 23.6	$ 21.7	$ 20.7	$ 25.7	$ 62.0		$ 91.7		$ 45.4
Net income (loss) per common share:
Basic (in dollars per share)	$ (0.66)	$ 1.59	$ 1.19	$ 1.74	$ 1.44	$ 1.31	$ 1.24	$ 1.54	$ 3.88		$ 5.53		$ 2.67
Net Income (loss) per common share, Diluted:
Diluted (in dollars per share)	(0.66)	1.57	1.18	1.71	1.41	1.29	1.22	1.51	3.83		5.43		2.63
Dividends declared per common share (in dollars per share)	$ 0.60	$ 0.60	$ 0.60	$ 0.60	$ 0.55	$ 0.55	$ 0.55	$ 0.55	$ 2.40		$ 2.20		$ 2.00
Goodwill impairment	$ 25.2						$ 18.4		$ 25.2		$ 0.0		$ 18.4
Loss on extinguishment of debt									$ (20.3)		$ 0.0		$ 0.0

[1] See Note 8 for discussion of our adoption of ASU 2017-12 (as defined in Note 1) in 2018 and the related reclassification of amounts in 2017 that were presented in the Statements of Consolidated Income within Unrealized (gain) loss on derivative instruments and are now presented within Cost of products sold, excluding depreciation and amortization and other items ("Cost of products sold").