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STOCK AWARD PLANS - Narrative (Details) - USD ($)	12 Months Ended
STOCK AWARD PLANS - Narrative (Details) - USD ($)	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual term of award (in years)	10 years
Options granted (in shares)	374,029	0	779,740
Compensation cost for stock options	$ 1,147,000	$ 1,571,000	$ 1,875,000
Stock Option Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost for stock options, net of forfeitures	$ 2,799,268
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity instruments other than options, nonvested (in shares)	538,911	568,987	495,782	489,777
Fair market value at date of grant at restricted stock	$ 13,709,896
Compensation cost for stock options	$ 5,061,000	$ 5,695,000	$ 4,512,000
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	3 years
Minimum \| Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	1 year
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	5 years
Maximum \| Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	7 years
2020 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant (in shares)	3,250,000
Shares available for issuance (in shares)	2,631,367