Stock-based Compensation - Narrative (Details) $ / shares in Units, $ in Thousands			1 Months Ended	3 Months Ended		9 Months Ended
	Jan. 01, 2025 shares	Nov. 16, 2023 USD ($) grantee $ / shares shares	Jun. 30, 2021	Sep. 30, 2025 USD ($) shares	Sep. 30, 2024 USD ($) shares	Sep. 30, 2025 USD ($) $ / shares shares	Sep. 30, 2024 USD ($) $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation cost related to unvested awards not yet recognized | $				$ 29,800		$ 29,800
Expected weighted-average period compensation cost to be recognized						2 years 1 month 6 days
Clinical development milestones, probable achievement (in shares)				33,617		33,617
Total stock-based compensation expense | $				$ 5,232	$ 7,622	$ 16,260	$ 25,061
RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
PSUs vested (in shares)						111,994
Stock option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share) | $ / shares						$ 8.93	$ 27.00
Stock option | 2023
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Minimum exercise price of plan modifications (in dollars per share) | $ / shares		$ 47.40
Original exercise price lower range (in dollars per share) | $ / shares		52.20
Original exercise price upper range (in dollars per share) | $ / shares		$ 359.00
Share-based payment arrangement, plan modification, number of grantees affected | grantee		200
Shares repriced (in shares)		1,170,843
Plan modification, exercise price (in dollars per share) | $ / shares		$ 37.40
Incremental stock-based compensation expense of modifications | $		$ 8,900
Performance Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award performance period						3 years
Service period from the milestone achievement date						1 year
Total stock-based compensation expense | $				$ 200	$ 0	$ 800	$ 200
PSUs vested (in shares)						33,623
Performance Shares | Achievement of applicable milestone
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting rights, percentage						50.00%
Performance Shares | Earlier of one year of service from achievement date and three-year performance period
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting rights, percentage						50.00%
Performance-Based Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award expiration period						10 years
Award performance period						3 years
Service period from the milestone achievement date						1 year
Performance-Based Stock Options | Achievement of applicable milestone
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting rights, percentage						50.00%
Performance-Based Stock Options | Earlier of one year of service from achievement date and three-year performance period
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting rights, percentage						50.00%
Minimum | Performance Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance period relative to total shareholder return						2 years
Awards granted, percentage of target						0.00%
Minimum | Performance-Based Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance period relative to total shareholder return						2 years
Awards granted, percentage of target						0.00%
Maximum | Performance Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance period relative to total shareholder return						3 years
Awards granted, percentage of target						200.00%
Maximum | Performance-Based Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance period relative to total shareholder return						3 years
Awards granted, percentage of target						200.00%
2021 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of additional shares authorized for issuance (in shares)	737,188
Increase in proportion of common shares reserved for future issuance (as a percent)	5.00%
Future issuance of common shares (in shares)				2,310,205		2,310,205
2021 Plan | RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			4 years
2021 Plan | Stock option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			4 years
2021 Plan | Performance Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			3 years
2021 Plan | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award expiration period			10 years
2021 ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of additional shares authorized for issuance (in shares)	0
Purchase of common stock at discount (as a percent)			15.00%
Employee purchase of shares, proportion of fair value (as a percent)			85.00%
Stock-based compensation (in shares)				26,062	24,565	26,062	24,565
Future issuance of common shares (in shares)				226,570		226,570