Leases - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended		9 Months Ended
	Oct. 31, 2022	Sep. 30, 2021	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Leases [Line Items]
ROU asset			$ 25,343		$ 25,343		$ 31,633
Lease liability			32,888		32,888
Operating lease costs			2,600	$ 1,200	7,700	$ 4,100
Cash paid for operating lease			800	1,100	3,900	3,200
Variable lease costs			$ 200	$ 1,500	$ 900	$ 3,600
Operating lease, weighted average remaining lease term			6 years 4 months 13 days		6 years 4 months 13 days		6 years 11 months 4 days
Operating lease, weighted average discount rate, percent			6.23%		6.23%		6.23%
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. At September 30, 2023, the Company has no reasonable certainty that this option to extend will be exercised.
Tenant improvement allowance to be reimbursed		$ 3,100
Tenant improvement allowance, reimbursement period		2 years
Tenant improvement allowance			$ 900		$ 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