Equity Incentive Plans and Stock-Based Compensation - Schedule of Option Activity Under the 2015 Plan and 2020 Plan (Details) - Incentive Stock Options and Nonqualified Stock Options - 2015 Equity and 2020 Incentive Plan - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2025	Dec. 31, 2024
Number of Options
Outstanding, beginning balance (in shares)	8,300,804
Granted (in shares)	2,271,680
Exercised (in shares)	(4,921)
Forfeited (in shares)	(2,479,046)
Outstanding, ending balance (in shares)	8,088,517	8,300,804
Number of options, exercisable (in shares)	5,108,451
Number of options, vested and expected to vest (in shares)	8,088,517
Weighted- Average Exercise Price per Share
Outstanding, beginning balance (USD per share)	$ 17.23
Granted (USD per share)	9.68
Exercised (USD per share)	12.18
Forfeited (USD per share)	16.43
Outstanding, ending balance (USD per share)	15.36	$ 17.23
Weighted- average exercise price per share, exercisable (USD per share)	16.29
Weighted- average exercise price per share, vested and expected to vest (USD per share)	$ 15.36
Weighted- Average Remaining Contractual Term (in Years)
Weighted- average remaining contractual term (in years), outstanding	6 years 11 months 26 days	7 years 5 months 26 days
Weighted- average remaining contractual term (in years), exercisable	5 years 11 months 19 days
Weighted- average remaining contractual term (in years), vested and expected to vest	6 years 11 months 26 days
Aggregate intrinsic value, outstanding balance	$ 0	$ 13,769
Aggregate intrinsic value, exercisable	0
Aggregate intrinsic value, vested and expected to vest	$ 0