DEBT Debt (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Jul. 31, 2023	Jul. 31, 2022
Debt Instrument
Shelf Notes	$ 75,000
Unsecured Debt	75,000	$ 50,000
Letters of Credit Outstanding, Amount	1,000	1,000
Line of Credit [Member]
Debt Instrument
Maximum borrowing capacity	45,000
Maximum borrowing capacity for letters of credit	$ 10,000
Expiration date	Aug. 30, 2027
Line of credit amount outstanding	$ 0	0
Series B Senior Notes
Debt Instrument
Starting payments	May 15, 2021
Face amount	$ 10,000
Annual rate	3.95%
Ending payments	May 15, 2030
Notes Payable	$ 7,000	8,000
Series C Senior Notes
Debt Instrument
Starting payments	Dec. 16, 2021
Face amount	$ 25,000
Annual rate	3.25%
Ending payments	Dec. 16, 2031
Notes Payable	$ 25,000	$ 25,000
Prime Rate \| Line of Credit [Member]
Debt Instrument
Variable interest rate	8.50%
Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate \| Line of Credit [Member]
Debt Instrument
Variable interest rate	5.37%

Maximum aggregate principal of unsecured notes available for purchase, at lender's discretion on an uncommitted basis.

No definition available.

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Namespace Prefix:	odc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

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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.

+ References

No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

Latest date the outstanding debt instruments are required to be repaid, in YYYY-MM-DD format.

+ References

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Definition

Earliest date the outstanding debt instruments are required to be repaid, in YYYY-MM-DD format.

+ References

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- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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.

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Period Type:	instant

- Definition

The maximum amount of borrowing capacity under a line of credit that is available as of the balance sheet date for a specific purpose other than for financing goods acquired for inventory or imminent delivery to a customer.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Date the credit facility terminates, in YYYY-MM-DD format.

+ References

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

The effective interest rate at the end of the reporting period.

+ References

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
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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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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Period Type:	instant

- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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Period Type:	instant

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