STOCK-BASED COMPENSATION (Details 2) - USD ($)	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance Share Award, Total Shareholder Return Percent	50.00%
Performance Share Award Cycle	3
Performance Share Award, Net Income Percent	50.00%
Black-Sholes Option-Pricing Model
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield	1.32%	1.60%
Risk-free interest rate	4.07%	1.93%
Expected volatility of Olin common stock	47.00%	48.00%
Expected life (years)	7 years	7 years
Weighted-average grant fair value (per option)	$ 28.74	$ 21.18
Weighted-average exercise price	$ 60.55	$ 49.71
Options granted	562,124	737,100
Monte Carlo Simulation Model
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	4.46%	1.74%
Expected volatility of Olin common stock	52.00%	59.00%
Expected life (years)	3 years	3 years
Expected average volatility of peer companies	0.42	0.47
Average correlation coefficient of peer companies	0.51	0.51
Grant date fair value (TSR based award)	$ 86.98	$ 64.13
Grant date fair value (net income based award)	$ 60.55	$ 49.71
Awards granted	161,474	184,000

The term (in years) of performance share awards.

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The grant date fair value of the net income portion of the performance share award.

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Percent of performance share awards that is based on net income.

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The grant date fair value of the total shareholder return portion of the performance share award.

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Percent of performance share awards that is based on total shareholder return.

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Net number of performance share awards granted during the period.

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Share Based Compensation Arrangements Expected Volatility Rate of Peer Companies

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Share Based Compensation Average Correlation Coefficient of Peer Companies

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(ii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
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-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Net number of share options (or share units) granted during the period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(01)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(01)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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