DEBT Debt (Narrative) (Details) - USD ($)	12 Months Ended
	Jul. 31, 2022	Jul. 31, 2021
Debt Instrument
Shelf Notes	$ 75,000,000
Letters of Credit Outstanding, Amount	964,000	$ 964,000
Series A Senior Notes
Debt Instrument
Face amount		18,500,000
Repayments of Debt		$ 3,100,000
Minimum overdue financial obligation considered as default	5,000,000
Debt Instrument, Maturity Date Range, Start		Aug. 01, 2019
Debt Instrument, Maturity Date Range, End		Jul. 31, 2020
Debt Instrument, Interest Rate, Stated Percentage		3.96%
Series B Senior Notes
Debt Instrument
Face amount	10,000,000
Minimum overdue financial obligation considered as default	5,000,000
Annual Principal Installments	$ 1,000,000
Debt Instrument, Maturity Date Range, Start	May 15, 2021
Debt Instrument, Maturity Date Range, End	May 15, 2030
Debt Instrument, Interest Rate, Stated Percentage	3.95%
Series C Senior Notes
Debt Instrument
Face amount	$ 25,000,000
Annual Principal Installments	$ 5,000,000
Debt Instrument, Maturity Date Range, Start	Dec. 16, 2021
Debt Instrument, Maturity Date Range, End	Dec. 16, 2031
Debt Instrument, Interest Rate, Stated Percentage	3.25%
Line of Credit, BMO Harris
Debt Instrument
Expiration date	Jan. 31, 2024
Maximum borrowing capacity	$ 45,000,000
Maximum borrowing capacity for letters of credit	$ 10,000,000
Variable interest rate, prime based	5.75%
Variable interest rate, LIBOR based	4.04%
Line of credit amount outstanding	$ 0	$ 0
Minimum overdue financial obligation considered as default	$ 1,000,000