CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOW - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Cash flows from operating activities:
Net loss	$ (29,361)	$ (23,050)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	726	811
Amortization and premium of marketable securities, net	(1,256)	772
Gain on fair value remeasurement of contingent consideration	0	(536)
Stock-based compensation expense	4,340	3,153
Changes in operating assets and liabilities:
Accounts and other receivables	(967)	(71)
Prepaid and other current assets	2,722	(7,148)
Accounts payable and accrued expenses	(3,448)	(2,738)
Other liabilities	(1,325)	4,273
Net cash used in operating activities	(28,569)	(24,534)
Cash flows from investing activities:
Sales and maturities of marketable securities	127,000	27,845
Purchases of marketable securities	(73,846)	(16,890)
Acquisition of property and equipment	(585)	(575)
Net cash provided by investing activities	52,569	10,380
Cash flows from financing activities:
Proceeds from issuance of stock from employee benefit plans	694	304
Net cash provided by financing activities	694	304
Net increase (decrease) in cash and cash equivalents	24,694	(13,850)
Cash and cash equivalents at beginning of period	29,429	39,143
Cash and cash equivalents at end of period	54,123	25,293
Non-cash investing activities
Accrued construction in progress	$ 134	$ 53