Exercise price per share or per unit of warrants or rights outstanding.

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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The cash outflow for cost incurred directly with the issuance of an equity security.

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The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

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The cash inflow associated with the amount received from holders exercising their stock warrants.

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Number of shares issued during the period as a result of the conversion of convertible securities.

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Number of new stock issued during the period.

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Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

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Value of input used to measure outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur.

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Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The number of warrants or rights issued during period.

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The net cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

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Note 19 - Subsequent Events (Details Textual)			3 Months Ended	12 Months Ended
Note 19 - Subsequent Events (Details Textual)	Mar. 02, 2020 USD ($) yr $ / shares shares	Mar. 20, 2019 USD ($) shares	Mar. 17, 2020 USD ($) shares	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Stock Issued During Period, Shares, New Issues \| shares		1,200,000
Payments of Stock Issuance Costs \| $		$ 320,000
Proceeds from Warrant Exercises \| $				$ 180,000
Subsequent Event [Member]
Stock Issued During Period, Shares, Conversion of Convertible Securities \| shares			18,472,183
Proceeds from Warrant Exercises \| $			$ 9,800,000
Subsequent Event [Member] \| The March 2020 Offering Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights \| shares	2,000,000
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right \| shares	1
Class of Warrant or Right, Exercise Price of Warrants or Rights \| $ / shares	$ 2.50
Warrants and Rights Outstanding, Term	5 years
Subsequent Event [Member] \| The March 2020 Offering Placement Agent Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right \| shares	1
Class of Warrant or Right, Exercise Price of Warrants or Rights \| $ / shares	$ 3.125
Warrants and Rights Outstanding, Term	5 years
Class of Warrant or Right, Issued During Period \| shares	280,000
Warrants and Rights Outstanding \| $	$ 453,000
Subsequent Event [Member] \| The March 2020 Offering Placement Agent Warrants [Member] \| Measurement Input, Share Price [Member]
Warrants and Rights Outstanding, Measurement Input	2.34
Subsequent Event [Member] \| The March 2020 Offering Placement Agent Warrants [Member] \| Measurement Input, Option Volatility [Member]
Warrants and Rights Outstanding, Measurement Input	0.98
Subsequent Event [Member] \| The March 2020 Offering Placement Agent Warrants [Member] \| Measurement Input, Risk Free Interest Rate [Member]
Warrants and Rights Outstanding, Measurement Input	0.0088
Subsequent Event [Member] \| The March 2020 Offering Placement Agent Warrants [Member] \| Measurement Input, Expected Dividend Rate [Member]
Warrants and Rights Outstanding, Measurement Input	0
Subsequent Event [Member] \| The March 2020 Offering Placement Agent Warrants [Member] \| Measurement Input, Expected Term [Member]
Warrants and Rights Outstanding, Measurement Input \| yr	4.99
Subsequent Event [Member] \| The March 2020 Offering [Member]
Stock Issued During Period, Shares, New Issues \| shares	4,000,000
Proceeds from Issuance or Sale of Equity, Total \| $	$ 10,000,000
Proceeds from Issuance or Sale of Equity, Net \| $	9,100,000
Payments of Stock Issuance Costs \| $	$ 775,000