CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Operating activities
Net loss	$ (40,928)	$ (36,684)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	9,385	7,873
Depreciation and amortization	879	687
Premiums and discounts on available-for-sale marketable securities	(1,326)	1,175
Changes in operating assets and liabilities:
Prepaid expenses and other assets	(1,641)	(586)
Contract asset—due from related parties	(783)	1,128
Accounts payable	2,217	(1,437)
Accrued expenses and other current liabilities	(10,037)	(2,278)
Deferred revenue	(6,145)	(8,359)
Operating lease right-of-use assets	1,138	119
Operating lease liabilities	2,915	(227)
Other assets and liabilities	358	550
Net cash (used in) provided by operating activities	(43,968)	(40,295)
Investing activities
Purchase of property and equipment, net	(4,009)	(482)
Purchases of investments	(61,835)	(80,118)
Maturities of investments	90,428	106,463
Net cash used in investing activities	24,584	25,863
Financing activities
Proceeds from stock option exercises	1,486	449
Payments on finance leases	(327)	(264)
Net cash provided by financing activities	1,159	185
Net (decrease) increase in cash, cash equivalents and restricted cash	(18,225)	(14,247)
Cash, cash equivalents and restricted cash at beginning of period	74,524	54,092
Cash, cash equivalents and restricted cash at end of period	56,299	39,845
Supplemental disclosure of cash flow activities
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	48,833	0
Cash paid for interest	52	46
Supplemental disclosure of noncash investing and financing activities
Property and equipment purchases included in accounts payable and accrued expenses	1,100	126
Cash and cash equivalents	50,152	33,733
Restricted cash	6,147	6,112
Total cash, cash equivalents, and restricted cash	$ 56,299	$ 39,845