Supplemental Balance Sheet Information - Summary of Other Noncurrent Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Sep. 30, 2023
Schedule Of Investments [Line Items]
Other assets	$ 4,464	$ 3,864
Operating Lease Right-of-Use Assets [Member]
Schedule Of Investments [Line Items]
Other assets	3,435	2,987
Other [Member]
Schedule Of Investments [Line Items]
Other assets	$ 1,029	$ 877