Stock-based Compensation - Narrative (Details) $ / shares in Units, $ in Thousands			1 Months Ended	3 Months Ended	12 Months Ended
	Jan. 01, 2024 shares	Nov. 16, 2023 USD ($) grantee $ / shares shares	Jun. 30, 2021 shares	Dec. 31, 2022 USD ($)	Dec. 31, 2024 USD ($) $ / shares shares	Dec. 31, 2023 USD ($) $ / shares shares	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2018 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation cost related to unvested awards not yet recognized | $					$ 44,700
Expected weighted-average period compensation cost to be recognized					2 years 3 months 18 days
Clinical development milestones, probable achievement (in shares)					1,500,000
Total stock-based compensation expense | $					$ 33,144	$ 47,084	$ 81,924
Weighted average grant date fair value (in dollars per share) | $ / shares					$ 1.30	$ 1.69	$ 3.60
Intrinsic value of options exercised | $					$ 2,900	$ 6,500	$ 13,900
Stock option | 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum exercise price of plan modifications (in dollars per share) | $ / shares		$ 2.37
Original exercise price lower range (in dollars per share) | $ / shares		2.61
Original exercise price upper range (in dollars per share) | $ / shares		$ 17.95
Share-based payment arrangement, plan modification, number of grantees affected | grantee		200
shares repriced (in shares)		23,416,860
Plan modification, exercise price (in dollars per share) | $ / shares		$ 1.87
Incremental stock-based compensation expense of modifications | $		$ 8,900
Stock option | 2022 | Previous CEO
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incremental stock-based compensation expense of modifications | $				$ 3,700
RSAs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards outstanding (in shares)					0	0
Fair value of awards vested during period | $					$ 0	$ 0	15,200
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards outstanding (in shares)					5,623,819	2,072,855
Fair value of awards vested during period | $					$ 2,000	$ 1,400	1,500
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award performance period					3 years
Service period from the milestone achievement date					1 year
Total stock-based compensation expense | $					$ 1,900	$ 0	$ 0
Awards outstanding (in shares)					2,703,400	0
Performance Shares | Share-Based Payment Arrangement, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage					50.00%
Maximum | Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period relative to total shareholder return					3 years
Awards granted, percentage of target					200.00%
Minimum | Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period relative to total shareholder return					2 years
Awards granted, percentage of target					0.00%
2021 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares reserved for future issuance (in shares)			26,662,087
Award expiration period			10 years
Proportion of stock outstanding (as a percent)			5.00%
Number of additional shares authorized for issuance (in shares)	12,697,885
Increase in proportion of common shares reserved for future issuance (as a percent)	5.00%
Vesting period			4 years
Future issuance of common shares (in shares)					41,180,525
2021 Plan | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award expiration period			10 years
2021 ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares reserved for future issuance (in shares)			2,470,000
Award expiration period			10 years
Proportion of stock outstanding (as a percent)			1.00%			1.00%
Number of additional shares authorized for issuance (in shares)	2,539,577
Future issuance of common shares (in shares)					5,046,445
Purchase of common stock at discount (as a percent)			15.00%
Purchase price in relation to common stock price (as a percent)			85.00%
Maximum number of shares to be purchased under ESPP (in shares)			4,940,000
Maximum offering period			27 months
Awards issued during period (in shares)					954,761	986,391	475,363
2018 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award expiration period								10 years
Vesting period								4 years
Future issuance of common shares (in shares)								0