Investments - Summary of Fair Value of Investments Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022
Assets:
Short-term investments:	$ 44,814	$ 58,268
Long-term investments:	5,674	10,633
Total assets at fair value	50,488	68,901
Current liabilities:
Acquisition-related contingent consideration	6,250	5,920
Total liabilities at fair value	6,250	5,920
U.S. Treasury
Assets:
Short-term investments:	3,921	5,882
Long-term investments:	3,224	3,221
Commercial paper
Assets:
Short-term investments:	15,429	18,022
Foreign government and agency securities
Assets:
Short-term investments:	2,842	2,827
Corporate debt securities
Assets:
Short-term investments:	22,622	31,537
Long-term investments:	2,450	7,412
Quoted Prices in Active Markets (Level 1)
Assets:
Short-term investments:	3,921	5,882
Long-term investments:	3,224	3,221
Total assets at fair value	7,145	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:	3,921	5,882
Long-term investments:	3,224	3,221
Quoted Prices in Active Markets (Level 1) \| Commercial paper
Assets:
Short-term investments:	0	0
Quoted Prices in Active Markets (Level 1) \| Foreign government and agency securities
Assets:
Short-term investments:	0	0
Quoted Prices in Active Markets (Level 1) \| Corporate debt securities
Assets:
Short-term investments:	0	0
Long-term investments:	0	0
Significant Other Observable Inputs (Level 2)
Assets:
Short-term investments:	40,893	52,386
Long-term investments:	2,450	7,412
Total assets at fair value	43,343	59,798
Current liabilities:
Acquisition-related contingent consideration	0	0
Total liabilities at fair value	0	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) \| Commercial paper
Assets:
Short-term investments:	15,429	18,022
Significant Other Observable Inputs (Level 2) \| Foreign government and agency securities
Assets:
Short-term investments:	2,842	2,827
Significant Other Observable Inputs (Level 2) \| Corporate debt securities
Assets:
Short-term investments:	22,622	31,537
Long-term investments:	2,450	7,412
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	6,250	5,920
Total liabilities at fair value	6,250	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) \| Commercial paper
Assets:
Short-term investments:	0	0
Significant Unobservable Inputs (Level 3) \| Foreign government and agency securities
Assets:
Short-term investments:	0	0
Significant Unobservable Inputs (Level 3) \| Corporate debt securities
Assets:
Short-term investments:	0	0
Long-term investments:	$ 0	$ 0

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