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Leases - Additional Information (Details)			1 Months Ended						3 Months Ended
Leases - Additional Information (Details)	Sep. 30, 2024 ft²	Jan. 31, 2024 ft²	Jul. 31, 2025 USD ($) ft²	Jul. 31, 2024 ft²	Apr. 30, 2022	Dec. 31, 2021 USD ($) ft²	Mar. 31, 2021 ft²	Sep. 30, 2020 USD ($) ft²	Mar. 31, 2026 USD ($)	Mar. 31, 2025 USD ($)	Dec. 31, 2025 USD ($)
Lessee Lease Description [Line Items]
Operating leases cancellable and non-cancellable expiration dates									2032
Total lease cost									$ 1,840,000	$ 2,261,000
Operating lease cost									1,799,000	1,831,000
Variable lease costs									751,000	1,143,000
Cash paid for operating leases									$ 1,500,000	1,500,000
Operating lease, weighted-average remaining lease term									6 years 1 month 24 days		6 years 4 months 20 days
Operating lease, weighted-average discount rate									8.99%		8.98%
Sublease income									$ (710,000)	(713,000)
Operating lease, aggregate monthly payments to lessor									60,391,000
Letter of credit provided to lessor									$ 408,000		$ 408,000
2020 Lease
Lessee Lease Description [Line Items]
Office space leases \| ft²								60,000
Lease commencement month and year								2021-08
Operating lease initial term								10 years 9 months
Operating lease, aggregate monthly payments to lessor								$ 51,600,000
Tenant improvement allowance								$ 16,800,000
Term for cancellation of lease								84 months
Notice period for cancellation of lease								12 months
Operating lease cancellation payment								$ 2,500,000
2020 Lease \| Letter of Credit
Lessee Lease Description [Line Items]
Letter of credit provided to lessor								$ 408,000
Line of credit facility, expiration date								Jul. 29, 2032
First Amendment to 2020 Lease
Lessee Lease Description [Line Items]
Office space leases \| ft²							18,000
Lease commencement month and year					2022-05		2022-02
2021 Lease
Lessee Lease Description [Line Items]
Office space leases \| ft²						30,000
Lease commencement month and year						2022-07
Operating lease initial term						124 months
Operating lease option to extend									5 years
Operating lease existence of option to extend [true false]									true
Operating lease, aggregate monthly payments to lessor						$ 34,400,000
Tenant improvement allowance						8,200,000
Security deposit paid			$ 656,000
2021 Lease \| Other Assets
Lessee Lease Description [Line Items]
Security deposit paid						$ 874,000			$ 218,000
2024 Lease
Lessee Lease Description [Line Items]
Sublease income									$ (710,000)	$ (713,000)
January 2024 Sublease
Lessee Lease Description [Line Items]
Facility lease termination description									In June 2025, the Company and the subtenant entered into a termination agreement that terminated the January 2024 Sublease in July 2025
Office space leases \| ft²		11,000
Lessor, Operating lease initial term		3 years
Lessor, Operating lease existence of option to extend [true false]		true
Lessor, Operating lease existence of option to terminate [true false]		true
July 2024 Sublease
Lessee Lease Description [Line Items]
Office space leases \| ft²				18,000
Lessor, Operating lease initial term				61 months
Lessor, Operating lease existence of option to terminate [true false]				true
September 2024 Sublease
Lessee Lease Description [Line Items]
Office space leases \| ft²	5,000
Operating lease initial term	1 year
Lessor, Operating lease existence of option to extend [true false]	true
Sublease extended term			Dec. 31, 2027
Amendment to september 2024 Sublease \| Laboratory Space
Lessee Lease Description [Line Items]
Office space leases \| ft²			5,000
Amendment to september 2024 Sublease \| Office Space
Lessee Lease Description [Line Items]
Office space leases \| ft²			11,000