INCOME TAXES (Details 4) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Valuation Allowance [Abstract]
Beginning balance	$ 76.4	$ 70.1
Increases to valuation allowances	23.6	14.6
Decreases to valuation allowances	(0.1)	(6.6)
Foreign currency translation adjustments	(0.4)	(1.7)
Ending balance	$ 99.5	$ 76.4

The change in deferred income tax valuation allowance due to the amount charged to the income tax provision during the period.

No definition available.

+ Details

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Period Type:	duration

- Definition

The change in deferred income tax valuation allowance due to the amount credited to the income tax provision (i.e. deduction from reserve) during the period.

+ References

No definition available.

+ Details

Name:	oln_Amountscreditedtoincometaxprovision
Namespace Prefix:	oln_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The currency translation adjustment impact on the valuation allowance.

+ References

No definition available.

+ Details

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Namespace Prefix:	oln_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-2

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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