INCOME TAXES (Details 4) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Valuation Allowance [Abstract]
Beginning balance	$ 239.6	$ 182.1
Increases to valuation allowances	3.2	54.6
Decreases to valuation allowances	(169.6)	(2.2)
Foreign currency translation adjustments	(3.1)	(5.1)
Ending balance	$ 70.1	$ 239.6

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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- 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

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Namespace Prefix:	oln_
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Balance Type:	debit
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- Definition

The currency translation adjustment impact on the valuation allowance.

+ References

No definition available.

+ Details

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- 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319

+ Details

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Period Type:	instant

- References

No definition available.

+ Details

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