Condensed Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Net income	$ 1.2	$ 47.8
Other comprehensive income, net of tax:
Foreign currency translation	(1.2)	(2.3)
Cash flow hedges	19.8	7.7
Pension and postretirement benefits	0.9	1.2
Total other comprehensive income, net of tax	19.5	6.6
Comprehensive income	20.7	54.4
Comprehensive loss attributable to noncontrolling interests	(0.2)	(0.8)
Comprehensive income attributable to Olin Corporation	$ 20.9	$ 55.2