STATEMENTS OF CONSOLIDATED INCOME (LOSS) - USD ($) shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Statement [Abstract]
Net sales	$ 3,087.0	$ 3,427.9	$ 2,622.0
Costs and expenses:
Cost of products sold, excluding depreciation and amortization	2,754.9	3,180.2	2,348.1
Depreciation and amortization	108.6	106.9	91.5
Selling, general, administrative, research and development	122.7	110.9	118.8
Goodwill impairment	0.0	20.5
Restructuring costs (benefit)	5.0	2.2	(0.8)
Other operating charges, net		3.2
Total costs and expenses	2,991.2	3,423.9	2,557.6
Operating income	95.8	4.0	64.4
Other (expense) income:
Interest expense	(46.9)	(48.3)	(49.5)
Other income (expense), net - Note 13	7.4	6.4	(38.9)
Income (loss) before income taxes	56.3	(37.9)	(24.0)
Income tax (provision) benefit	(9.1)	8.3	5.5
Net income (loss)	$ 47.2	$ (29.6)	$ (18.5)
Net income (loss) per common share:
Basic	$ 2.95	$ (1.86)	$ (1.17)
Diluted	$ 2.92	$ (1.86)	$ (1.17)
Weighted-average number of common shares outstanding (in thousands):
Basic	15,991	15,906	15,836
Diluted	16,131	15,906	15,836