Condensed Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Net income	$ 104.5	$ 315.2	$ 403.2	$ 1,130.3
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(3.3)	(25.1)	(6.3)	(61.6)
Gains (losses) on derivative contracts, net	6.2	(8.7)	21.0	(33.0)
Amortization of prior service costs and actuarial losses, net	0.2	7.0	0.9	20.3
Total other comprehensive income (loss), net of tax	3.1	(26.8)	15.6	(74.3)
Comprehensive income	107.6	288.4	418.8	1,056.0
Comprehensive income (loss) attributable to noncontrolling interests	0.4	0.0	(4.1)	0.0
Comprehensive income attributable to Olin Corporation	$ 107.2	$ 288.4	$ 422.9	$ 1,056.0