CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Operating activities
Net loss	$ (132,594)	$ (119,943)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	32,220	26,571
Depreciation and amortization	2,674	2,159
Premiums and discounts on available-for-sale marketable securities	(3,960)	1,794
Changes in operating assets and liabilities:
Prepaid expenses and other assets	(4,378)	(512)
Contract asset	(1,241)	(2,747)
Accounts payable	507	2,321
Accrued expenses and other current liabilities	(3,613)	1,677
Deferred revenue	(19,487)	(24,172)
Operating lease right-of-use assets	2,787	378
Operating lease liabilities	15,675	(738)
Other assets and liabilities	539	(337)
Net cash used in operating activities	(110,871)	(113,549)
Investing activities
Purchase of property and equipment, net	(22,855)	(2,463)
Purchases of investments	(143,647)	(298,736)
Maturities of investments	287,436	371,384
Net cash provided by investing activities	120,934	70,185
Financing activities
Proceeds from issuance of common stock and accompanying pre-funded warrants from private placement, net of issuance costs	0	149,825
Proceeds from stock option exercises	2,297	1,790
Proceeds from employee stock purchase plan	962	256
Payments on finance leases	(1,001)	(825)
Net cash provided by financing activities	2,258	151,046
Net increase in cash, cash equivalents and restricted cash	12,321	107,682
Cash, cash equivalents and restricted cash at beginning of period	74,524	54,092
Cash, cash equivalents and restricted cash at end of period	86,845	161,774
Supplemental disclosure of cash flow activities
Right-of-use assets obtained in exchange for new operating lease liabilities	48,833	0
Cash paid for interest	115	124
Supplemental disclosure of noncash investing and financing activities
Property and equipment purchases included in accounts payable and accrued expenses	2,762	340
Purchase of property and equipment through finance lease	0	87
Cash and cash equivalents	81,051	155,658
Restricted cash	5,794	6,116
Total cash, cash equivalents, and restricted cash	$ 86,845	$ 161,774