Equity Incentive Plans - Summary of Stock Option Activity Under 2009 Plan and 2019 Plan (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2022
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Shares Subject to Outstanding Stock Options, Stock Options outstanding, Beginning Balance	12,778,984
Shares Subject to Outstanding Stock Options, Stock Options granted	4,423,644
Shares Subject to Outstanding Stock Options, Stock Options forfeited or cancelled	(1,554,973)
Shares Subject to Outstanding Stock Options, Stock Options expired	(496,457)
Shares Subject to Outstanding Stock Options, Stock Options exercised	(1,361,891)
Shares Subject to Outstanding Stock Options, Stock Options outstanding, Ending Balance	13,789,307
Shares Subject to Outstanding Stock Options, Stock Options vested and exercisable	7,226,163
Weighted Average Exercise Price per Share, Stock Options outstanding, Beginning Balance	$ 19.72
Weighted Average Exercise Price per Share, Stock Options granted	11.67
Weighted Average Exercise Price per Share, Stock Options forfeited or cancelled	28.64
Weighted Average Exercise Price per Share, Stock Options expired	33.05
Weighted Average Exercise Price per Share, Stock Options exercised	5.55
Weighted Average Exercise Price per Share, Stock Options outstanding, Ending Balance	17.05
Weighted Average Exercise Price per Share, Stock Options vested and exercisable	$ 14.42
Aggregate Intrinsic Value, Stock Option outstanding	$ 4,183
Aggregate Intrinsic Value, Stock Options vested and exercisable	$ 4,178