CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) $ in Thousands	9 Months Ended
	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)
Operating activities
Net loss	$ (153,106)	$ (132,594)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	41,213	32,220
Lease impairment charge	4,925	0
Depreciation and amortization	5,386	2,674
Premiums and discounts on available-for-sale marketable securities	(10,716)	(3,960)
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(5,754)	(4,378)
Accounts receivable	15,000	0
Contract asset	2,445	(1,241)
Other long term assets	2,118	0
Accounts payable	198	507
Accrued expenses and other current liabilities	(4,842)	(3,613)
Deferred revenue	(34,627)	(19,487)
Operating lease right-of-use assets	1,883	2,787
Operating lease liabilities	3,048	15,675
Other assets and liabilities	112	539
Net cash used in operating activities	(132,717)	(110,871)
Investing activities
Purchase of property and equipment, net	(11,902)	(22,855)
Purchases of investments	(822,804)	(143,647)
Maturities of investments	362,061	287,436
Net cash (used in) provided by investing activities	(472,645)	120,934
Financing activities
Issuance of common stock and accompanying pre-funded warrants from January 2024 public offering, net of issuance costs	301,373	0
Proceeds from issuance of common stock through At-The Market Sales Agreement, net of issuance costs	48,740	0
Issuance of common stock and accompanying pre-funded warrants from August 2024 public offering, net of issuance costs	246,506	0
Proceeds from stock option exercises	9,616	2,297
Proceeds from employee stock purchase plan	1,134	962
Payments on finance leases	(1,283)	(1,001)
Net cash provided by financing activities	606,086	2,258
Net increase in cash, cash equivalents and restricted cash	724	12,321
Cash, cash equivalents and restricted cash at beginning of period	115,777	74,524
Cash, cash equivalents and restricted cash at end of period	116,501	86,845
Supplemental disclosure of cash flow activities
Right-of-use assets obtained in exchange for new operating lease liabilities	0	48,833
Cash paid for interest	144	115
Supplemental disclosure of noncash investing and financing activities
Property and equipment purchases included in accounts payable and accrued expenses	744	2,762
Purchase of property and equipment through finance lease	1,793	0
Cash and cash equivalents	110,718	81,051
Restricted cash	5,783	5,794
Total cash, cash equivalents, and restricted cash	$ 116,501	$ 86,845