Leases (Tables)

12 Months Ended

Dec. 31, 2021

Lessee Lease Description [Line Items]

Summary of Lease Term and Incremental Borrowing Rate Applied in Arriving at Lease Liability

The following table summarizes the lease term and incremental borrowing rate applied in arriving at the lease liability:

	As of December 31,
	2021			2020
Remaining lease term	10.2 years			7.3 years
Incremental borrowing rate		5.2	%		10.0	%

Undiscounted Minimum Future Lease Payments Under Non-cancelable Leases

Future lease payments under non-cancelable leases as of December 31, 2021 for each of the years ending December 31 are as follows (in thousands):

Undiscounted lease payments*:
2022	$	2,994
2023		3,491
2024		3,596
2025		3,704
2026		3,815
Thereafter		25,085
Total undiscounted lease payments		42,685
Less: imputed interest		(10,574	)
Total operating lease liability as of December 31, 2021	$	32,111

*As stated above, this table does not include lease payments for the Newly Leased Space under the Amended Lease as the commencement date is subsequent to December 31, 2021.

Watertown Lease

Lessee Lease Description [Line Items]

Summary of Lease Costs

The elements of lease costs were as follows (in thousands):

	Years Ended December 31,
	2021		2020		2019
Lease cost:
Operating lease cost	$	2,686	$	2,550	$	2,550
Variable lease cost		857		1,066		1,020
Total lease cost	$	3,543	$	3,616	$	3,570