Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Assets
Cash and cash equivalents	$ 9,637	$ 11,241
Restricted cash	169	169
Short-term investments	15,478	14,356
Accounts receivable, net	529	733
Inventories	1,941	2,130
Other inventory supplies	138	183
Prepaid expenses and other current assets	185	109
Assets held for sale	4,145	4,145
Total current assets	32,222	33,066
Property and equipment, net	2,717	2,728
Total assets	34,939	35,794
Liabilities and stockholders' equity
Accounts payable	367	400
Accrued payroll	479	28
Accrued and other current liabilities	294	345
Corporate income and franchise taxes	279	286
Accrued real estate taxes	126	96
Advance payments	16	39
Total current liabilities	1,561	1,194
Total liabilities	1,561	1,194
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; 2,925,957 and 2,919,542 shares issued; 2,677,167 and 2,733,601 shares outstanding	29	29
Additional paid-in capital	376,035	375,979
Treasury stock, at cost, 248,790 and 185,941 shares	(12,714)	(12,213)
Accumulated other comprehensive income (loss)	1	(2)
Accumulated deficit	(329,973)	(329,193)
Total stockholders' equity	33,378	34,600
Total liabilities and stockholders' equity	$ 34,939	$ 35,794