Leases - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended						12 Months Ended
	Jul. 31, 2024	Jun. 30, 2024	Feb. 29, 2024	Dec. 31, 2023	Oct. 31, 2022	Sep. 30, 2021	Dec. 31, 2024	Dec. 31, 2023
Leases [Line Items]
ROU asset				$ 2,187				$ 2,187
Operating lease costs							$ 600	9,700
Cash paid for operating lease							17,000	4,800
Variable lease costs							100	900
Impairment loss to operating lease right-of-use assets							$ 0	$ 16,600
Waltham Leases
Leases [Line Items]
Expiration date						Jul. 30, 2030
Lease commencement month and year						2021-09
New Lease Agreement with BP Bay Colony LLC
Leases [Line Items]
ROU asset						$ 6,000
Lease liability						6,000
Sublease Agreement with AMAG Pharmaceuticals Inc.
Leases [Line Items]
Lease, termination date		Jun. 30, 2024
ROU asset						17,300
Lease liability						$ 17,300
Termination fee paid		$ 5,700
Gain on termination of lease		$ 1,800
Termination Agreement with BP Bay Colony LLC
Leases [Line Items]
Termination fee paid	$ 7,000
Gain on termination of lease	$ 1,500
2022 SOW Under the DMS Agreement
Leases [Line Items]
Lease expiration month and year					2024-12
ROU asset					$ 14,700
Lease liability					14,700
Reduction to right-of-use asset and lease liability				$ 4,900
Utilization fee					$ 16,300
Lessee operating lease, lease term including renewal option					2 years 3 months
2024 SOW under the DMS Agreement
Leases [Line Items]
Gain on termination of lease			$ 5,600