INVESTMENTS - Summary of Fair Value of Investments Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Sep. 30, 2022
Assets:
Short-term investments:	$ 74,700	$ 58,268
Long-term investments:	1,304	10,633
Total assets at fair value	76,004	68,901
Current liabilities:
Acquisition-related contingent consideration	7,976	5,920
Total liabilities at fair value	7,976	5,920
U.S. Treasury
Assets:
Short-term investments:	40,254	5,882
Long-term investments:	1,304	3,221
Corporate debt securities
Assets:
Short-term investments:	34,446	31,537
Long-term investments:		7,412
Commercial paper
Assets:
Short-term investments:		18,022
Foreign government and agency securities
Assets:
Short-term investments:		2,827
Quoted Prices in Active Markets (Level 1)
Assets:
Short-term investments:	40,254	5,882
Long-term investments:	1,304	3,221
Total assets at fair value	41,558	9,103
Current liabilities:
Acquisition-related contingent consideration	0	0
Total liabilities at fair value	0	0
Quoted Prices in Active Markets (Level 1) | U.S. Treasury
Assets:
Short-term investments:	40,254	5,882
Long-term investments:	1,304	3,221
Quoted Prices in Active Markets (Level 1) | Corporate debt securities
Assets:
Short-term investments:	0	0
Long-term investments:		0
Quoted Prices in Active Markets (Level 1) | Commercial paper
Assets:
Short-term investments:		0
Quoted Prices in Active Markets (Level 1) | Foreign government and agency securities
Assets:
Short-term investments:		0
Significant Other Observable Inputs (Level 2)
Assets:
Short-term investments:	34,446	52,386
Long-term investments:	0	7,412
Total assets at fair value	34,446	59,798
Current liabilities:
Acquisition-related contingent consideration	7,976	0
Total liabilities at fair value	7,976	0
Significant Other Observable Inputs (Level 2) | U.S. Treasury
Assets:
Short-term investments:	0	0
Long-term investments:	0	0
Significant Other Observable Inputs (Level 2) | Corporate debt securities
Assets:
Short-term investments:	34,446	31,537
Long-term investments:		7,412
Significant Other Observable Inputs (Level 2) | Commercial paper
Assets:
Short-term investments:		18,022
Significant Other Observable Inputs (Level 2) | Foreign government and agency securities
Assets:
Short-term investments:		2,827
Significant Unobservable Inputs (Level 3)
Assets:
Short-term investments:	0	0
Long-term investments:	0	0
Total assets at fair value	0	0
Current liabilities:
Acquisition-related contingent consideration	0	5,920
Total liabilities at fair value	0	5,920
Significant Unobservable Inputs (Level 3) | U.S. Treasury
Assets:
Short-term investments:	0	0
Long-term investments:	0	0
Significant Unobservable Inputs (Level 3) | Corporate debt securities
Assets:
Short-term investments:	$ 0	0
Long-term investments:		0
Significant Unobservable Inputs (Level 3) | Commercial paper
Assets:
Short-term investments:		0
Significant Unobservable Inputs (Level 3) | Foreign government and agency securities
Assets:
Short-term investments:		$ 0