Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Assets
Cash and cash equivalents	$ 10,882	$ 8,709
Restricted cash		171
Short-term investments	14,743	15,458
Accounts receivable, net	579	1,053
Inventories	1,236	1,710
Other inventory supplies	141	140
Prepaid expenses and other current assets	255	488
Assets held for sale	1,011	3,957
Total current assets	28,847	31,686
Inventories, non-current	468	468
Property and equipment, net	2,566	2,647
Total assets	31,881	34,801
Liabilities and stockholders' equity
Accounts payable	355	733
Accrued payroll	56	53
Accrued and other current liabilities	209	344
Corporate income and franchise taxes	298	296
Accrued real estate taxes	71	114
Advance payments		16
Total current liabilities	989	1,556
Total liabilities	989	1,556
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; 2,955,253 and 2,955,253 shares issued; 2,472,393 and 2,702,171 shares outstanding, respectively	29	29
Additional paid-in capital	376,319	376,306
Treasury stock, at cost, 482,860 and 253,082 shares	(14,617)	(12,749)
Accumulated other comprehensive income (loss)	(1)	(1)
Accumulated deficit	(330,838)	(330,340)
Total stockholders' equity	30,892	33,245
Total liabilities and stockholders' equity	$ 31,881	$ 34,801