Leases - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended				3 Months Ended
	Feb. 29, 2024	Dec. 31, 2023	Oct. 31, 2022	Sep. 30, 2021	Mar. 31, 2024	Mar. 31, 2023
Leases [Line Items]
ROU asset		$ 2,187			$ 2,107
Lease liability					18,342
Gain on termination of lease					5,583
Operating lease costs					400	$ 2,600
Impairment loss to operating lease right-of-use assets		$ 16,600			0	0
Remaining right-of-use asset balance					2,100
Cash paid for operating lease					3,800	2,100
Variable lease costs					$ 100	$ 100
Operating lease, weighted average remaining lease term		4 years 8 months 12 days			6 years 3 months 29 days
Operating lease, weighted average discount rate, percent		5.95%			5.00%
Waltham Leases
Leases [Line Items]
Expiration date				Jul. 30, 2030
Operating lease, existence of option to extend				true
Lease, option to extend					The Company has the option to renew the leased space for an additional one time period of five years with written notice from the Company. As of March 31, 2024, the Company has no reasonable certainty that this option to extend will be exercised.
Tenant improvement allowance to be reimbursed				$ 3,100	$ 900
Lease commencement month and year				2021-09
Additional one time lease period				5 years
New Lease Agreement with BP Bay Colony LLC
Leases [Line Items]
ROU asset				$ 6,000
Lease liability				6,000
Sublease with AMAG Pharmaceuticals
Leases [Line Items]
ROU asset				17,300
Lease liability				$ 17,300
2022 SOW Under the DMS Agreement
Leases [Line Items]
Lease expiration month and year			2024-12
ROU asset			$ 14,700
Lease liability			14,700
Utilization fee			$ 16,300
Lessee operating lease, lease term including renewal option			2 years 3 months
Reduction to right-of-use asset and lease liability		$ 4,900
2024 SOW Under the DMS Agreement
Leases [Line Items]
Gain on termination of lease	$ 5,600