Note 6 - Long-term Debt and Notes Payable (Details Textual) - USD ($)	6 Months Ended	12 Months Ended
Apr. 30, 2025	Oct. 31, 2024
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration]	Prime Rate [Member]	Prime Rate [Member]
Revolving Credit Facility [Member] \| SLR Business Credit [Member]
Debt Instrument Minimum Interest Applicable Rate	4.75%
Debt Instrument, Interest Rate, Effective Percentage	9.00%	9.50%
Line of Credit Facility, Percent of Eligible Accounts	85.00%
Line of Credit Facility, Percent of Eligible Inventory	35.00%
Line of Credit Facility, Additional Capacity for Advances	$ 7,000,000
Line of Credit Facility, Maximum Percentage of Outstanding Eligible Accounts Loan Value	100.00%
Line of Credit Facility, Restricted Capacity for Advances	$ 1,150,000
Line of Credit Facility, Maximum Borrowing Capacity	$ 18,000,000
Debt Instrument, Basis Spread on Variable Rate	1.50%
Debt Instrument Default Interest Above Applicable Rate	6.00%
Long-Term Line of Credit	$ 6,500,000	$ 8,300,000
Line of Credit Facility, Remaining Borrowing Capacity	$ 2,600,000	$ 3,200,000
Virginia Real Estate Loan [Member]
Debt Instrument, Term (Month)	240 months
Debt Instrument Minimum Interest Applicable Rate	8.50%
Debt Instrument, Interest Rate, Effective Percentage	7.50%	8.00%
Long-Term Debt	$ 2,600,000	$ 2,600,000

Represents default interest above the applicable rate.

No definition available.

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

- Definition

Represents the minimum interest applicable rate.

+ References

No definition available.

+ Details

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

- Definition

Additional facility for advances.

+ References

No definition available.

+ Details

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

- Definition

Percent of maximum outstanding eligible accounts loan value available for advance.

+ References

No definition available.

+ Details

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

- Definition

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

+ References

No definition available.

+ Details

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

- Definition

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

+ References

No definition available.

+ Details

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

- Definition

Additional limit to facility for advances.

+ References

No definition available.

+ Details

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

- Definition

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

+ References

No definition available.

+ Details

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

- Definition

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

+ References

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+ Details

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

- Definition

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.

+ References

No definition available.

+ Details

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

- Definition

Indicates type of variable interest rate on debt instrument.

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+ Details

Name:	us-gaap_DebtInstrumentVariableInterestRateTypeExtensibleEnumeration
Namespace Prefix:	us-gaap_
Data Type:	enum2:enumerationSetItemType
Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

+ Details

Name:	us-gaap_LineOfCredit
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

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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).

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

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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

- Details

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

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=occ_SLRBusinessCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=occ_VirginiaRealEstateLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: