Fair Value of Financial Instruments - Summary of Fair Values of Financial Instruments (Detail) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Financial assets carried at fair value:
Cash equivalents, fair value disclosure	$ 35,841	$ 40,479
Short-term investments, available for sale	880,093	306,563
Total financial assets	915,934	347,042
Level 1 [Member]
Financial assets carried at fair value:
Cash equivalents, fair value disclosure	35,841	16,411
Total financial assets	35,841	16,411
Level 2 [Member]
Financial assets carried at fair value:
Cash equivalents, fair value disclosure		24,068
Total financial assets	880,093	330,631
Commercial paper, available-for-sale [Member]
Financial assets carried at fair value:
Short-term investments, available for sale	14,550	24,226
Commercial paper, available-for-sale [Member] | Level 2 [Member]
Financial assets carried at fair value:
Short-term investments, available for sale	14,550	24,226
Corporate debt securities, available-for-sale [Member]
Financial assets carried at fair value:
Short-term investments, available for sale	692,572	168,584
Corporate debt securities, available-for-sale [Member] | Level 2 [Member]
Financial assets carried at fair value:
Short-term investments, available for sale	692,572	168,584
Government debt securities [Member]
Financial assets carried at fair value:
Short-term investments, available for sale	172,971	113,753
Government debt securities [Member] | Level 2 [Member]
Financial assets carried at fair value:
Short-term investments, available for sale	$ 172,971	$ 113,753