Note 7 - Commitments and Contingencies (Details Textual) - USD ($)	Mar. 31, 2019	Jan. 01, 2019
Operating Lease, Right-of-Use Asset	$ 1,131,000	$ 1,258,000
Operating Lease, Liability, Total	$ 1,131,000	$ 1,258,000
Operating Lease, Weighted Average Discount Rate, Percent	5.50%
Operating Lease, Weighted Average Remaining Lease Term	2 years