Leases - Additional Information (Detail) $ in Thousands		1 Months Ended			9 Months Ended
	Feb. 28, 2022 USD ($) ft²	Jun. 30, 2022 USD ($) ft²	Feb. 28, 2022 USD ($) ft²	Jan. 31, 2022 USD ($) ft²	Sep. 30, 2022 USD ($) ft²	Jan. 01, 2023 USD ($)	Dec. 31, 2021 USD ($)
Lessee Lease Description [Line Items]
Operating lease right-of-use assets					$ 101,290		$ 79,143
Prepaid lease payments					$ 500
730 Main Lease [Member]
Lessee Lease Description [Line Items]
Area of space leased | ft²					38,000
Operating lease, description					In January 2022, the Company entered into an agreement to lease approximately 38,000 square feet of office and laboratory space at 730 Main Street, Cambridge, Massachusetts under an operating lease agreement (the “730 Main Lease”). The initial term of the 730 Main Lease is
Term of lease				10 years
Base rent per square foot for first year | ft²				130.00
Letter of credit				$ 2,400
Operating lease, options to extend					the Company has the option to extend the 730 Main Lease for one five-year term.
Percentage of Annual Increase					3.00%
Albany Lease [Member]
Lessee Lease Description [Line Items]
Operating lease, existence of option to extend					true
840 Winter Street Lease [Member]
Lessee Lease Description [Line Items]
Area of space leased | ft²	140,000
Operating lease, description			In February 2022, the Company entered into an agreement to lease approximately 140,000 square feet of manufacturing space located at 840 Winter Street, Waltham, Massachusetts (the “840 Winter Lease”), which will provide the Company with the ability to manufacture its own products in a good manufacturing practice (“GMP”) compliant facility as well as to supplement the Company’s current leased premises in Cambridge, Massachusetts. The 840 Winter Lease, including the obligation to pay rent, is expected to commence in the second half of 2024 for an
Term of lease	12 years		12 years
Base rent per square foot for first year | ft²			73.50
Letter of credit	$ 2,600		$ 2,600
Operating lease, options to extend					The Company has the option to extend the 840 Winter Lease for two five-year terms.
Percentage of Annual Increase					3.00%
840 Winter Street Lease [Member] | forecast Member
Lessee Lease Description [Line Items]
Letter of credit						$ 6,000
MemorialDrive640Member
Lessee Lease Description [Line Items]
Area of space leased | ft²		62,000
Operating lease, description		In June 2022, the Company entered into an agreement to lease approximately 62,000 square feet of office and laboratory space located at 640 Memorial Drive, Cambridge, Massachusetts under an operating lease agreement (the “640 Memorial Drive Lease”). The term of the lease is five years, ending in August 2027. The Company does not have an option to extend the 640 Memorial Drive Lease. The base rent under the 640 Memorial Drive Lease is approximately $97 per square foot per year during the first year of the term, which is subject to scheduled 4% annual increases, plus certain operating expenses and taxes. In September 2022 the Company determined, in accordance with ASC 842, that the commencement date for the lease had been met as the lessor had made the space available for the Company's use
Term of lease		5 years
Base rent per square foot for first year | ft²		0.97
Operating lease right-of-use assets					$ 30,700
Operating lease, liability					$ 30,200
Incremental borrowing rate					7.99%
Letter of credit					$ 1,800
cost of tenant improvements		$ 1,200
Operating lease, options to extend					The Company does not have an option to extend the 640 Memorial Drive Lease.
Percentage of Annual Increase					4.00%