Name:	occ_DebtInstrumentTermExtensions
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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Additional facility for advances.

No definition available.

Name:	occ_LineOfCreditFacilityAdditionalCapacityForAdvances
Namespace Prefix:	occ_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Percent of aggregate outstanding amount of eligible accounts available for advance.

No definition available.

Name:	occ_LineOfCreditFacilityPercentOfEligibleAccounts
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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Percent of aggregate outstanding amount of eligible inventory available for advance.

No definition available.

Name:	occ_LineOfCreditFacilityPercentOfEligibleInventory
Namespace Prefix:	occ_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Additional limit to facility for advances.

No definition available.

Name:	occ_LineOfCreditFacilityRestrictedCapacityForAdvances
Namespace Prefix:	occ_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Contractual interest rate for funds borrowed, under the debt agreement.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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Balance Type:	na
Period Type:	instant

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	us-gaap_DebtInstrumentTerm
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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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

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.

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

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

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

Name:	us-gaap_LineOfCreditFacilityAxis=occ_PinnacleFinancialPartnersMember
Namespace Prefix:
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Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_LongtermDebtTypeAxis=occ_VirginiaRealEstateLoanAndNorthCarolinaRealEstateLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_LineOfCreditFacilityAxis=occ_NorthMillCapitalLlcMember
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Name:	srt_RangeAxis=srt_MaximumMember
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