Note 6 - Leases - Lease Cost and Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Operating lease cost, net of impairment	$ 406,000	$ 351,000
Sublease income	(174,000)	(14,000)
Total lease cost	232,000	337,000
Cash paid for amounts included in the measurement of lease liabilities - Operating leases	$ 406,000	$ 351,000
Weighted-average remaining lease term - Operating leases in years (Year)	1 year 1 month 9 days	1 year 4 months 20 days
Weighted-average discount rate - Operating leases	5.65%	5.80%