Note 8 - Leases - Lease Assets and Liabilities (Details) - USD ($)	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Operating Lease, Right-of-Use Asset	$ 395,000	$ 629,000
Accrued Liabilities [Member]
Current operating lease liabilities	268,000	230,000
Other Noncurrent Liabilities [Member]
Noncurrent operating lease liabilities	132,000	399,000
Accrued Liabilities and Other Noncurrent Liabilities [Member]
	$ 400,000	$ 629,000