Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Current assets
Cash and cash equivalents	$ 20,536	$ 82,647
Investment securities, available-for-sale	62,173	32,720
Inventory	1,861	1,780
Advance to Ibeo	4,132	0
Other current assets	2,306	2,283
Total current assets	91,008	119,430
Property and equipment, net	6,830	3,026
Operating lease right-of-use asset	14,579	5,577
Restricted cash	1,418	1,092
Intangible assets, net	75	115
Other assets	1,086	985
Total assets	114,996	130,225
Current liabilities
Accounts payable	2,061	3,584
Accrued liabilities	2,058	1,170
Contract liabilities	4,601	5,265
Other current liabilities	839	1,181
Current portion of long-term debt	0	392
Current portion of operating lease liability	1,846	849
Current portion of finance lease obligations	21	21
Total current liabilities	11,426	12,462
Operating lease liability, net of current portion	13,829	4,983
Finance lease obligations, net of current portion	0	26
Total liabilities	25,255	17,471
Commitments and contingencies (Note 14)
Shareholders' equity
Preferred stock, par value $0.001; 25,000 shares authorized; zero and zero shares issued and outstanding, respectively	0	0
Common stock, par value $0.001; 210,000 shares authorized; 170,503 and 164,363 shares issued and outstanding at December 31, 2022 and 2021, respectively	171	164
Additional paid-in capital	772,221	742,042
Accumulated other comprehensive loss	(127)	(19)
Accumulated deficit	(682,524)	(629,433)
Total shareholders' equity	89,741	112,754
Total liabilities and shareholders' equity	$ 114,996	$ 130,225