CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Statement [Abstract]
Sales	$ 8,910.6	$ 5,758.0	$ 6,110.0
Operating expenses:
Cost of goods sold	6,616.4	5,374.6	5,439.2
Selling and administration	416.9	422.0	416.9
Restructuring charges	27.9	9.0	76.5
Goodwill impairment	0.0	699.8	0.0
Other operating income	1.4	0.7	0.4
Operating income (loss)	1,850.8	(746.7)	177.8
Interest expense	348.0	292.7	243.2
Interest income	0.2	0.5	1.0
Non-operating pension income	35.7	18.9	16.3
Other income	0.0	0.0	11.2
Income (loss) before taxes	1,538.7	(1,020.0)	(36.9)
Income tax provision (benefit)	242.0	(50.1)	(25.6)
Net income (loss)	$ 1,296.7	$ (969.9)	$ (11.3)
Net income (loss) per common share:
Basic	$ 8.15	$ (6.14)	$ (0.07)
Diluted	$ 7.96	$ (6.14)	$ (0.07)
Average common shares outstanding:
Basic	159.1	157.9	162.3
Diluted	163.0	157.9	162.3