Condensed Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2023		134,781,286
Beginning balance at Dec. 31, 2023	$ 1,590,236	$ 13	$ 1,828,862	$ (815)	$ (237,824)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Vesting of restricted common stock (in shares)		1,321,120
Vesting of restricted common stock	1	$ 1
Exercise of stock options (in shares)		288,113
Exercise of stock options	701		701
Issuance of common stock under employee stock purchase plan (in shares)		315,831
Issuance of common stock under employee stock purchase plan	2,602		2,602
Stock-based compensation	62,616		62,616
Other comprehensive income (loss)	1,942			1,942
Net loss	(417,371)				(417,371)
Ending balance (in shares) at Sep. 30, 2024		136,706,350
Ending balance at Sep. 30, 2024	1,240,727	$ 14	1,894,781	1,127	(655,195)
Beginning balance (in shares) at Jun. 30, 2024		136,590,097
Beginning balance at Jun. 30, 2024	1,433,670	$ 14	1,878,013	(2,879)	(441,478)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Vesting of restricted common stock (in shares)		81,415
Vesting of restricted common stock	0
Exercise of stock options (in shares)		34,838
Exercise of stock options	71		71
Stock-based compensation	16,697		16,697
Other comprehensive income (loss)	4,006			4,006
Net loss	(213,717)				(213,717)
Ending balance (in shares) at Sep. 30, 2024		136,706,350
Ending balance at Sep. 30, 2024	$ 1,240,727	$ 14	1,894,781	1,127	(655,195)
Beginning balance (in shares) at Dec. 31, 2024	136,959,446	136,959,446
Beginning balance at Dec. 31, 2024	$ 1,150,385	$ 14	1,911,872	(1,717)	(759,784)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Vesting of restricted common stock (in shares)		1,366,748
Vesting of restricted common stock	0
Exercise of stock options (in shares)		298,060
Exercise of stock options	1,348		1,348
Issuance of common stock under employee stock purchase plan (in shares)		398,340
Issuance of common stock under employee stock purchase plan	1,757		1,757
Stock-based compensation	37,866		37,866
Other comprehensive income (loss)	(194)			(194)
Net loss	$ (395,064)				(395,064)
Ending balance (in shares) at Sep. 30, 2025	139,022,594	139,022,594
Ending balance at Sep. 30, 2025	$ 796,098	$ 14	1,952,843	(1,911)	(1,154,848)
Beginning balance (in shares) at Jun. 30, 2025		138,886,274
Beginning balance at Jun. 30, 2025	947,472	$ 14	1,941,386	(2,221)	(991,707)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Vesting of restricted common stock (in shares)		69,063
Vesting of restricted common stock	0
Exercise of stock options (in shares)		67,257
Exercise of stock options	101		101
Stock-based compensation	11,356		11,356
Other comprehensive income (loss)	310			310
Net loss	$ (163,141)				(163,141)
Ending balance (in shares) at Sep. 30, 2025	139,022,594	139,022,594
Ending balance at Sep. 30, 2025	$ 796,098	$ 14	$ 1,952,843	$ (1,911)	$ (1,154,848)