Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Assets
Cash and cash equivalents	$ 10,571	$ 11,130
Short-term investments	14,749	14,748
Accounts receivable, net	389	386
Inventories	1,046	1,073
Other inventory supplies	138	140
Prepaid expenses and other current assets	253	284
Assets held for sale	529	529
Total current assets	27,675	28,290
Inventories, non-current	468	468
Property and equipment, net	2,441	2,482
Total assets	30,584	31,240
Liabilities and stockholders’ equity
Accounts payable	309	497
Accrued payroll	153	211
Accrued and other current liabilities	385	201
Corporate income and franchise taxes	329	307
Accrued real estate taxes	90	71
Advance payments	11	18
Total current liabilities	1,277	1,305
Total liabilities	1,277	1,305
Commitments and contingencies (Note 7)
Stockholders’ equity
Preferred stock, $.001 par value, 1,000,000 undesignated shares authorized, no shares issued or outstanding
Common stock, $.001 par value, 8,200,000 shares authorized; 2,987,883 and 2,971,283 shares issued; 2,438,855 and 2,422,255 shares outstanding, respectively	29	29
Additional paid-in capital	376,635	376,456
Treasury stock, at cost, 549,028 and 549,028 shares	(15,147)	(15,147)
Accumulated other comprehensive income
Accumulated deficit	(332,210)	(331,403)
Total stockholders’ equity	29,307	29,935
Total liabilities and stockholders’ equity	$ 30,584	$ 31,240