Condensed Statements of Operations - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Income Statement [Abstract]
Sales	$ 1,644.2	$ 1,635.3
Operating expenses:
Cost of goods sold	1,495.5	1,428.0
Selling and administrative	101.0	101.9
Restructuring charges	4.0	8.3
Other operating income	0.0	0.2
Operating income	43.7	97.3
Interest expense	48.5	44.6
Interest income	1.2	0.8
Non-operating pension income	5.7	6.8
Income before taxes	2.1	60.3
Income tax provision	0.9	12.5
Net income	1.2	47.8
Net loss attributable to noncontrolling interests	(0.2)	(0.8)
Net income attributable to Olin Corporation	$ 1.4	$ 48.6
Net income attributable to Olin Corporation per common share:
Basic	$ 0.01	$ 0.41
Diluted	$ 0.01	$ 0.40
Weighted-average common shares outstanding:
Basic	115.3	119.9
Diluted	116.6	121.9