Fair Value Measurements - Summary of Financial Assets that are Measured at Fair Value and Indicates the Fair Value Hierarchy of the Valuation Inputs (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Sep. 30, 2021
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value	$ 105,016	$ 118,612
Estimated fair value of cash and cash equivalents	68,749	78,838
Marketable Securities	34,267	37,774
Money Market Funds | Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value	67,558	75,873
Estimated fair value of cash and cash equivalents	67,558	75,873
Time Deposits | Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value	1,191	2,965
Estimated fair value of cash and cash equivalents	1,191	2,965
Commercial Paper | Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value	19,373	18,080
Marketable Securities	19,373	18,080
Corporate Debt Securities | Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value	14,894	19,694
Marketable Securities	14,894	19,694
Debt Securities | Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value	$ 2,000	$ 2,000