Consolidated Balance Sheets (Current Period Unuaudited) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Current Assets:
Cash and cash equivalents	$ 11,008	$ 13,331
Restricted cash	25	25
Marketable securities	7,760	5,956
Ownership interests	0	860
Prepaid expenses and other current assets	1,345	1,251
Total current assets	20,138	21,423
Right-of-use asset, net	1,215	1,290
Ownership interests and advances	11,991	14,545
Other assets	383	434
Total Assets	33,727	37,692
Current Liabilities:
Accounts payable	71	16
Accrued compensation and benefits	99	507
Accrued expenses and other current liabilities	539	865
Lease liability - current	443	429
Total current liabilities	1,152	1,817
Lease liability - non-current	1,133	1,249
Other long-term liabilities	50	50
Total Liabilities	2,335	3,116
Commitments and contingencies (Note 9)
Equity:
Preferred stock, $0.10 par value; 1,000 shares authorized	0	0
Common stock, $0.10 par value; 83,333 shares authorized; 21,573 shares issued and outstanding at March 31, 2023 and December 31, 2022	2,157	2,157
Additional paid-in capital	803,021	804,752
Treasury stock, at cost; 5,310 and 5,478 shares at March 31, 2023 and December 31, 2022, respectively	(46,379)	(48,410)
Accumulated deficit	(727,382)	(723,898)
Accumulated other comprehensive loss	(25)	(25)
Total Equity	31,392	34,576
Total Liabilities and Equity	$ 33,727	$ 37,692