Fair Value Measurements - Summary of Financial Assets that are Measured at Fair Value and Indicates the Fair Value Hierarchy of the Valuation Inputs (Parenthetical) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Sep. 30, 2021
Time Deposits
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities, cost	$ 1,191	$ 2,965
Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities, cost	19,371	18,080
Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities, cost	15,074	19,704
Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities, cost	$ 2,000	$ 2,000