Condensed Statements of Operations - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Income Statement [Abstract]
Sales	$ 1,702.7	$ 2,616.1	$ 3,547.0	$ 5,077.5
Operating expenses:
Cost of goods sold	1,392.6	1,951.4	2,834.3	3,758.9
Selling and administration	101.2	99.0	213.0	203.3
Restructuring charges	19.2	3.6	80.1	6.7
Other operating income	27.0	3.3	27.5	3.3
Operating income	216.7	565.4	447.1	1,111.9
Interest expense	45.3	34.5	87.7	67.4
Interest income	1.1	0.3	2.2	0.7
Non-operating pension income	5.4	9.5	11.1	19.1
Income before taxes	177.9	540.7	372.7	1,064.3
Income tax provision	33.2	118.6	74.0	249.2
Net income	144.7	422.1	298.7	815.1
Net loss attributable to noncontrolling interests	(2.2)	0.0	(4.5)	0.0
Net income attributable to Olin Corporation	$ 146.9	$ 422.1	$ 303.2	$ 815.1
Net income attributable to Olin Corporation per common share:
Basic	$ 1.15	$ 2.83	$ 2.35	$ 5.37
Diluted	$ 1.13	$ 2.76	$ 2.29	$ 5.24
Average common shares outstanding:
Basic	127.4	149.2	129.2	151.9
Diluted	130.4	152.8	132.4	155.6