Stock-Based Compensation - Stock Option Activity (Details) - Employee Stock Option - $ / shares	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Shares
Options outstanding at beginning of the period (in shares)	5,085,662
Granted (in shares)	1,553,275
Exercised (in shares)	(50,773)
Canceled (in shares)	(180,580)
Options outstanding at the end of the period (in shares)	6,407,584	5,085,662
Options vested and expected to vest at the end of the period (in shares)	6,271,198
Options exercisable at the end of the period (in shares)	3,088,826
Shares available for grant under the 2021 Plan	1,065,273
Weighted Average Exercise Price Per Share
Options outstanding at beginning of the period (in dollars per share)	$ 29.26
Granted (in dollars per share)	36.88
Exercised (in dollars per share)	15.89
Canceled (in dollars per share)	87.57
Options outstanding at the end of the period (in dollars per share)	29.57	$ 29.26
Options vested and expected to Vest at the end of the period (in dollars per share)	29.54
Options exercisable at the end of the period (in dollars per share)	$ 29.58
Weighted Average Remaining Contractual Term (In Years)
Options outstanding at the end of the period	7 years 9 months 18 days	7 years 10 months 24 days
Options vested and expected to vest at the end of the period	7 years 8 months 12 days
Options exercisable at the end of the period	6 years 7 months 6 days