Income Taxes - Summary of Company's Net Deferred Tax Assets (Liabilities) (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred tax assets:
Net operating loss carryforwards	$ 258,664	$ 229,375
Research and development credit carryforwards	151,333	101,326
Section 174 capitalized research	150,993	78,873
Operating lease liability	31,183	35,386
Deferred revenue	9,633	13,189
Equity-based compensation	30,408	22,512
Accruals and allowances	6,244	4,968
Prepaid Rent	1,190	1,367
Equity investment adjustments	7,580	3,358
Intangibles, including acquired in-process research and development	1,017	930
Capitalized start-up costs	249	296
Gross deferred tax assets	648,494	491,580
Deferred tax asset valuation allowance	(616,082)	(454,793)
Total deferred tax assets	32,412	36,787
Deferred tax liabilities:
Fixed assets	(1,221)	(759)
Operating lease right-of-use assets	(31,191)	(36,028)
Total deferred tax liabilities	(32,412)	(36,787)
Net deferred tax asset (liability)	$ 0	$ 0