Stock-Based Compensation - Summary of Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	9 Months Ended
Jun. 30, 2025	Sep. 30, 2024
Number of Shares
Beginning balance (in shares)	394,493
Granted (in shares)	33,185
Forfeited (in shares)	(120,053)
Ending balance (in shares)	307,625
Number of shares Options, Exercisable (in shares)	121,016
Number of shares Options, Vested and expected to vest (in shares)	264,099
Weighted Average Exercise Price
Beginning balance (in usd per share)	$ 57.09
Granted (in usd per share)	9.87
Forfeited (in usd per share)	33.42
Ending balance (in usd per share)	61.24
Weighted average exercise price, Exercisable (in usd per share)	112.56
Weighted average exercise price, Vested and expected to vest (in usd per share)	$ 67.02
Weighted average contractual term outstanding (in years)	8 years 2 months 12 days	8 years 7 months 6 days
Weighted average contractual term outstanding, Exercisable (in years)	6 years 10 months 24 days
Weighted average contractual term outstanding, Vested and expected to vest (in years)	7 years 10 months 24 days
Aggregate intrinsic value, Beginning balance	$ 269
Aggregate intrinsic value, Ending balance	0
Aggregate intrinsic value, exercisable	0
Aggregate intrinsic value, vested and expected to vest	0
Aggregate intrinsic value, forfeited and expired	$ 0

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.