Note 11 - Commitments and Contingencies (Details Textual)	3 Months Ended	6 Months Ended
Jun. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)
Operating Lease, Expense	$ 14,700	$ 29,400
Operating Lease, Weighted Average Remaining Lease Term	1 year 182 days	1 year 182 days
Operating Lease, Weighted Average Discount Rate, Percent	12.00%	12.00%
Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year	$ 29,000	$ 29,000
Lessee, Operating Lease, Liability, Payments, Due Year Two	44,000	44,000
Lessee, Operating Lease, Liability, Payments, Due Year Three	12,000	12,000
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	11,500	11,500
Operating Lease, Payments	$ 14,200	$ 28,800

Amount of lessee's undiscounted obligation for lease payments for operating lease, due in third fiscal year following latest fiscal year.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.

+ References

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Amount of operating lease expense. Excludes sublease income.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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