Stock Plans and Stock Based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2022	Dec. 31, 2021
Number of Shares
Beginning balance (in shares)	10,363,769
Granted (in shares)	4,694,350
Exercised (in shares)	0
Canceled/Forfeited (in shares)	(472,820)
Ending balance (in shares)	14,585,299	10,363,769
Exercisable at end of period (in shares)	7,398,636
Vested and unvested expected to vest at end of period (in shares)	13,783,730
Weighted Average Exercise Price per Share
Beginning balance (in dollars per share)	$ 3.80
Granted (in dollars per share)	3.14
Exercised (in dollars per share)	0
Canceled/Forfeited (in dollars per share)	7.29
Ending balance (in dollars per share)	3.47	$ 3.80
Exercisable at end of period (in dollars per share)	3.32
Vested and unvested expected to vest at end of period (in dollars per share)	$ 3.46
Weighted Average Remaining Contractual Life
Outstanding at end of period	7 years 8 months 23 days	7 years 4 months 28 days
Exercisable at end of period	6 years 6 months 18 days
Vested and unvested expected to vest at end of period	7 years 7 months 20 days
Aggregate Intrinsic Value
Outstanding at end of period	$ 19
Exercisable at end of period	11
Vested and unvested expected to vest at end of period	$ 18