2021 Senior Credit Facility

No definition available.

Name:	oln_A2021SeniorCreditFacility
Namespace Prefix:	oln_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the 2021 $315.0 million delayed-draw term loan facility, which is included in the 2021 Senior Secured Credit Facility.

+ References

No definition available.

+ Details

Name:	oln_DelayedDrawTermLoanFacilityMaximumBorrowingCapacity
Namespace Prefix:	oln_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of the letter of credit subfacility issued under the 2020 $800.0 million senior secured revolving credit facility.

+ References

No definition available.

+ Details

Name:	oln_LetterofCreditSubfacilityMaximum
Namespace Prefix:	oln_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

$500.0 million Senior Term Loan Facility

+ References

No definition available.

+ Details

Name:	oln_SeniorTermLoanFacility
Namespace Prefix:	oln_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Expense recognized for the write-off of deferred debt issuance costs and deferred fair value interest rate swap losses as a result of the retirement of debt prior to its maturity date.

+ References

No definition available.

+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- 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.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=123467658&loc=d3e12355-112629

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=123467658&loc=d3e12317-112629

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

+ Details

Name:	us-gaap_GainsLossesOnExtinguishmentOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The total of the cash outflow during the period which has been paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt and the cost incurred directly for the issuance of equity securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3291-108585

+ Details

Name:	us-gaap_PaymentOfFinancingAndStockIssuanceCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3291-108585

+ Details

Name:	us-gaap_PaymentsOfDebtExtinguishmentCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3255-108585

+ Details

Name:	us-gaap_ProceedsFromIssuanceOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3291-108585

+ Details

Name:	us-gaap_RepaymentsOfLongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_DebtInstrumentAxis=oln_A16500MillionSeniorCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=oln_A3150MillionSeniorDelayedDrawTermLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=oln_A5000MillionSeniorTermLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=oln_A8000MillionSeniorRevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=oln_A1000SeniorNotesDue2025Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=oln_SeniorTermLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

DEBT (Details 1) - USD ($) $ in Millions		3 Months Ended	6 Months Ended
DEBT (Details 1) - USD ($) $ in Millions	Mar. 30, 2021	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Mar. 31, 2021	Feb. 24, 2021
Debt Instrument [Line Items]
Long-term Debt Repayments			$ (115.5)	$ (855.2)
Loss on Debt Extinguishment		$ (15.4)	0.0	38.9
Payment for Debt Extinguishment or Debt Prepayment Cost		12.3	0.0	31.0
Write-off of Deferred Debt Issuance Costs and Deferred Fair Value Interest Rate Swap Losses		$ 3.1		7.9
Debt issuance costs			0.0	3.1
$1,615.0 million Senior Credit Facility
Debt Instrument [Line Items]
2021 Senior Credit Facility						$ 1,615.0
$315.0 million Senior Delayed Draw Term Loan
Debt Instrument [Line Items]
Senior Delayed-Draw Term Loan, Maximum Borrowing Capacity						315.0
Proceeds from Issuance of Debt	$ 315.0
$500.0 million Senior Term Loan
Debt Instrument [Line Items]
Senior Term Loan Facility						500.0
$800.0 million Senior Revolving Credit Facility
Debt Instrument [Line Items]
Senior Revolving Credit Facility, Maximum Borrowing Capacity						800.0
Letter of Credit Subfacility, Maximum						$ 100.0
Senior Revolving Credit Facility, Remaining Borrowing Capacity			799.6
Letters of Credit Outstanding, Amount			$ 0.4
10.00% Senior Notes Due 2025
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					10.00%
Senior Term Loans
Debt Instrument [Line Items]
Long-term Debt Repayments				$ (465.0)