Fair value measurement - Summary of Company's Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Assets
Money market funds	$ 378,687	$ 465,829
Total financial assets	443,086	442,472
Liabilities
Contingent consideration	11,692	9,856
Total financial liabilities	11,692	9,856
Commercial paper
Assets
Short term investments, fair value	14,997
U.S. government treasury bills
Assets
Short term investments, fair value	111,284	12,034
Money market funds
Assets
Money market funds	316,805	430,438
Level 1
Assets
Total financial assets	428,089	442,472
Liabilities
Contingent consideration	0	0
Total financial liabilities	0	0
Level 1 \| Commercial paper
Assets
Short term investments, fair value	0
Level 1 \| U.S. government treasury bills
Assets
Short term investments, fair value	111,284	12,034
Level 1 \| Money market funds
Assets
Money market funds	316,805	430,438
Level 2
Assets
Total financial assets	14,997	0
Liabilities
Contingent consideration	9,592	9,856
Total financial liabilities	9,592	9,856
Level 2 \| Commercial paper
Assets
Short term investments, fair value	14,997
Level 2 \| U.S. government treasury bills
Assets
Short term investments, fair value	0	0
Level 2 \| Money market funds
Assets
Money market funds	0	0
Level 3
Assets
Total financial assets	0	0
Liabilities
Contingent consideration	2,100	0
Total financial liabilities	2,100	0
Level 3 \| Commercial paper
Assets
Short term investments, fair value	0
Level 3 \| U.S. government treasury bills
Assets
Short term investments, fair value	0	0
Level 3 \| Money market funds
Assets
Money market funds	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount of liability recognized arising from contingent consideration in a business combination.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value of financial and nonfinancial obligations.

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