INVESTMENTS - Investments by Type of Security (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Sep. 30, 2024
Debt Securities, Available-for-sale [Line Items]
Cost	$ 48,218	$ 48,141
Gross Unrealized Gains	58	161
Gross Unrealized Losses	(25)	(8)
Fair Market Value	48,251	48,294
Short-Term | U.S. Government and agency securities, short-term
Debt Securities, Available-for-sale [Line Items]
Cost	1,488
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Fair Market Value	1,488
Short-Term | U.S. Treasury, short-term
Debt Securities, Available-for-sale [Line Items]
Cost		3,841
Gross Unrealized Gains		1
Gross Unrealized Losses		(6)
Fair Market Value		3,836
Short-Term | Commercial paper, short-term
Debt Securities, Available-for-sale [Line Items]
Cost	17,286	15,964
Gross Unrealized Gains	0	20
Gross Unrealized Losses	(12)	0
Fair Market Value	17,274	15,984
Short-Term | Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Cost	21,164	17,008
Gross Unrealized Gains	29	56
Gross Unrealized Losses	(8)	0
Fair Market Value	21,185	17,064
Long Term Investments | Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Cost	7,780	11,328
Gross Unrealized Gains	29	84
Gross Unrealized Losses	(4)	(2)
Fair Market Value	7,805	$ 11,410
Long Term Investments | U.S. Government and agency securities, long-term
Debt Securities, Available-for-sale [Line Items]
Cost	500
Gross Unrealized Gains	0
Gross Unrealized Losses	(1)
Fair Market Value	$ 499