Income Taxes - Components of Net Deferred Tax Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred tax assets:
Net operating loss carryforwards	$ 192,179	$ 154,888
Capitalized research and development	101,136	49,687
Tax credit carryforwards	69,070	44,051
Lease liabilities	31,503	28,050
Stock-based compensation	12,607	6,958
Intangibles	10,744	7,949
Accrued liabilities and allowances	6,050	6,807
Fixed assets	1,073
Success payment liabilities	496	516
Other	285	155
Gross deferred tax assets	425,143	299,061
Valuation allowance	(402,658)	(274,348)
Deferred tax assets, net of valuation allowance	22,485	24,713
Deferred tax liabilities:
Right-of-use assets	$ (22,485)	(23,554)
Fixed assets		$ (1,159)