CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Cash flows from operating activities:
Net loss	$ (112,325)	$ (70,511)	$ (59,780)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	2,896	3,068	3,929
Amortization and premium of marketable securities, net	844	(3,209)	(729)
Loss (gain) on sale or disposal of assets	2	(24)	(55)
Intangible asset impairment		3,500	18,000
Gain on fair value remeasurement of contingent consideration	(6,862)	(1,405)	(4,218)
Non-cash income tax benefit		(227)	(1,167)
Stock-based compensation expense	15,611	8,953	3,915
Changes in operating assets and liabilities:
Accounts and other receivables	(175)	1,574	(787)
Prepaid and other current assets	(9,572)	(1,871)	(334)
Other assets		(5)
Accounts payable and accrued expenses	3,123	3,653	1,638
Other liabilities	2,726	(4,405)	(816)
Net cash used in operating activities	(103,732)	(60,909)	(40,404)
Cash flows from investing activities:
Sales and maturities of marketable securities	280,666	174,947	123,600
Purchases of marketable securities	(188,965)	(389,881)	(220,321)
Acquisition of property and equipment	(1,828)	(1,249)	(1,552)
Proceeds from sale or disposal of assets	69	27	55
Net cash provided by (used in) investing activities	89,942	(216,156)	(98,218)
Cash flows from financing activities:
Net proceeds from stock issuances		269,893	170,792
Proceeds from issuance of stock from employee benefit plans	4,076	2,479	434
Issuance of term loan			2,962
Payment of term loan			(2,962)
Net cash provided by financing activities	4,076	272,372	171,226
Net (decrease) increase in cash and cash equivalents	(9,714)	(4,693)	32,604
Cash and cash equivalents at beginning of period	39,143	43,836	11,232
Cash and cash equivalents at end of period	29,429	39,143	43,836
Non-cash investing activities
Accrued construction in progress	$ 113	$ 289	$ 221