EBP, Participant Contribution, Pretax, Maximum Annual Compensation to Total Compensation, Percentage

80.00%

EBP, Participant Contribution, Automatic, Deferral Rate

6.00%

Automatic Escalation Percentage

100.00%

Automatic Escalation Percentage Maximum

1500.00%

Olin Common Stock Fund Maximum Allocation Percentage

2000.00%

Matching Contribution Immediate Vesting Percentage

10000.00%

Retirement Contribution Percentage Immediately Vested

300.00%

EBP, Forfeited Nonvested Account, Decrease from Employer Contribution | $

$ 1,518,789

$ 1,800,000

EBP, Forfeited Nonvested Account | $

144,082

$ 149,017

EBP, Note Receivable from Participant, Account, Maximum Borrowing, Amount | $

$ 50,000

EBP, Note Receivable from Participant, Account, Maximum Borrowing, to Total Account, Percentage

50.00%

Maximum Loan Term, Years | yr

Outstanding Loan Rate, Minimum

3.25%

Outstanding Loan Rate, Maximum

9.50%

8.50%

New Loan Rate, Minimum

7.00%

7.75%

New Loan Rate, Maximum

7.50%

8.50%

EBP, Plan Termination [Text Block]

Plan Termination

Although it has not expressed any intent to do so, Olin has the right under the Plan to terminate the Plan, subject to the provisions of ERISA. In the event of Plan termination, participants will become 100% vested in their accounts.

Less than 2 years of service [Member]

Retirement Contribution Vesting Percentage

0.00%

2 years of service [Member]

Retirement Contribution Vesting Percentage

5000.00%

3 years of service or more [Member]

Retirement Contribution Vesting Percentage

10000.00%

Automatic Escalation Percentage

No definition available.

Name:	oln_AutomaticEscalationPercentage
Namespace Prefix:	oln_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Automatic Escalation Percentage Maximum

No definition available.

Name:	oln_AutomaticEscalationPercentageMaximum
Namespace Prefix:	oln_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Matching Contribution Immediate Vesting Percentage

No definition available.

Name:	oln_MatchingContributionImmediateVestingPercentage
Namespace Prefix:	oln_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Maximum Loan Term, Years

No definition available.

Name:	oln_MaximumLoanTermYears
Namespace Prefix:	oln_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

New Loan Rate, Maximum

No definition available.

Name:	oln_NewLoanRateMaximum
Namespace Prefix:	oln_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

New Loan Rate, Minimum

No definition available.

Name:	oln_NewLoanRateMinimum
Namespace Prefix:	oln_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Olin Common Stock Fund Maximum Allocation Percentage

No definition available.

Name:	oln_OlinCommonStockFundMaximumAllocationPercentage
Namespace Prefix:	oln_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Outstanding Loan Rate, Maximum

No definition available.

Name:	oln_OutstandingLoanRateMaximum
Namespace Prefix:	oln_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Outstanding Loan Rate, Minimum

No definition available.

Name:	oln_OutstandingLoanRateMinimum
Namespace Prefix:	oln_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Retirement Contribution Percentage Immediately Vested

No definition available.

Name:	oln_RetirementContributionPercentageImmediatelyVested
Namespace Prefix:	oln_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Retirement Contribution Vesting Percentage

No definition available.

Name:	oln_RetirementContributionVestingPercentage
Namespace Prefix:	oln_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

Name:	us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems
Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amount of plan asset, in forfeited nonvested account, no longer allocated to participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

Name:	us-gaap-ebp_EmployeeBenefitPlanForfeitedNonvestedAccount
Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Amount of decrease in forfeited nonvested account of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) from employer contribution.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (j)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-04(5)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Amount of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

Name:	us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMaximumBorrowingAmount
Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Percentage of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow to total participant account balance.

Name:	us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMaximumBorrowingToTotalAccountPercentage
Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Percentage of eligible compensation contributed for participant automatically enrolled in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

Name:	us-gaap-ebp_EmployeeBenefitPlanParticipantContributionAutomaticDeferralRate
Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Percentage of maximum pretax annual compensation that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), is permitted to contribute to total pretax annual compensation.

Name:	us-gaap-ebp_EmployeeBenefitPlanParticipantContributionPretaxMaximumAnnualCompensationToTotalCompensationPercentage
Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

The entire disclosure for terminating employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), including, but not limited to, plan under which participant no longer accrues benefit but remains in existence to pay already accrued benefit.

Name:	us-gaap-ebp_EmployeeBenefitPlanPlanTerminationTextBlock
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Balance Type:	na
Period Type:	duration

Name:	dei_LegalEntityAxis=oln_EBP032Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	oln_RetirementSavingsPlanVestingAxis=oln_LessThan2YearsOfServiceMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	oln_RetirementSavingsPlanVestingAxis=oln_A2YearsOfServiceMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: