Leases - Additional Information (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Dec. 31, 2021	Oct. 01, 2021	Sep. 26, 2016	Apr. 30, 2015
Operating Leased Assets [Line Items]
Lease agreement term			5 years
Restricted cash	$ 3,651	$ 3,651
Lease option to extend description	In August 2022, the Company executed the second amendment to the Cambridge Lease with respect to the Cambridge Lease Extension.
Description of additional lease space	The lease for the additional space commenced on October 1, 2021, with a term of five years and, for accounting purposes, is considered a separate lease from the Cambridge Lease (the “Additional Cambridge Lease”).
Operating lease right-of-use assets	$ 28,791	18,378	$ 4,500
Operating lease liability			$ 4,500
Lexington, Massachusetts [Member]
Operating Leased Assets [Line Items]
Lease agreement term				10 years 9 months
Renewal options	10 year and 9-month lease , which includes two successive five-year renewal options
Restricted cash	$ 2,700	2,700
Lease renewal term				5 years
Cambridge, Massachusetts [Member]
Operating Leased Assets [Line Items]
Lease agreement term					7 years 6 months
Restricted cash	$ 1,000	$ 1,000
Lease option to extend description	five-year renewal option to extend the lease.
Option to extend the lease	true
Operating lease right-of-use assets	$ 12,000
Operating lease liability	$ 12,000
Incremental borrowing rate	10.53%
Lease renewal term	5 years				5 years