Note 5 - Commitments and Contingencies (Details Textual)	3 Months Ended	6 Months Ended
	Jun. 30, 2019 USD ($) ft²	Jun. 30, 2019 USD ($) ft²	Dec. 31, 2018 USD ($)
Area of Real Estate Property | ft²	7,495	7,495
Operating Lease, Expense	$ 68,000	$ 139,000
Operating Lease, Right-of-Use Asset	68,000	68,000
Operating Lease, Liability, Total	68,000	68,000
Security Deposit	22,000	22,000
Letters of Credit Outstanding, Amount	22,000	22,000	$ 22,000
Loans Pledged as Collateral	$ 22,000	$ 22,000	$ 22,000