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

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Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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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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Represents the number of votes per share of common stock.

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The exercise price per share or per unit of warrants necessary to be entitled to receive cash consideration equal to Black-Scholes valuation, as defined in the warrant, in the event of a Fundamental Transaction (a transfer of ownership of the Company as defined in the warrant)

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Note 10 - Stockholders' Equity (Details Textual)	9 Months Ended
Note 10 - Stockholders' Equity (Details Textual)	Sep. 30, 2019 USD ($) $ / shares shares	Apr. 23, 2019 $ / shares shares	Apr. 22, 2019 shares	Apr. 11, 2019 USD ($) $ / shares shares	Mar. 20, 2019 USD ($) $ / shares shares	Dec. 31, 2018 $ / shares shares
Preferred Stock, Shares Authorized \| shares	5,000,000					5,000,000
Preferred Stock, Par or Stated Value Per Share	$ 0.10					$ 0.10
Preferred Stock, Shares Outstanding, Ending Balance \| shares	0					0
Common Stock, Par or Stated Value Per Share	$ 0.10	$ 0.10				$ 0.10
Common Stock, Shares Authorized \| shares	100,000,000	100,000,000	200,000,000			100,000,000
Common Stock, Number of Votes Per Share		1
Dividends, Common Stock, Total \| $	$ 0
Warrants in Connection with March 2019 Offering [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					$ 3.125
Warrants and Rights Outstanding \| $					$ 100,000
Warrants in Connection with March 2019 Offering [Member] \| Measurement Input, Share Price [Member]
Warrants and Rights Outstanding, Measurement Input					2.08
Warrants in Connection with March 2019 Offering [Member] \| Measurement Input, Price Volatility [Member]
Warrants and Rights Outstanding, Measurement Input					0.8
Warrants in Connection with March 2019 Offering [Member] \| Measurement Input, Risk Free Interest Rate [Member]
Warrants and Rights Outstanding, Measurement Input					0.0234
Warrants in Connection with March 2019 Offering [Member] \| Measurement Input, Expected Dividend Rate [Member]
Warrants and Rights Outstanding, Measurement Input					0
Warrants in Connection with March 2019 Offering [Member] \| Measurement Input, Expected Term [Member]
Warrants and Rights Outstanding, Measurement Input					5
Warrants in Connection With the April 2019 Offering [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				$ 1.375
Warrants and Rights Outstanding \| $				$ 333,000
Warrants in Connection With the April 2019 Offering [Member] \| Measurement Input, Share Price [Member]
Warrants and Rights Outstanding, Measurement Input				0.89
Warrants in Connection With the April 2019 Offering [Member] \| Measurement Input, Price Volatility [Member]
Warrants and Rights Outstanding, Measurement Input				0.83
Warrants in Connection With the April 2019 Offering [Member] \| Measurement Input, Risk Free Interest Rate [Member]
Warrants and Rights Outstanding, Measurement Input				0.0231
Warrants in Connection With the April 2019 Offering [Member] \| Measurement Input, Expected Dividend Rate [Member]
Warrants and Rights Outstanding, Measurement Input				0
Warrants in Connection With the April 2019 Offering [Member] \| Measurement Input, Expected Term [Member]
Warrants and Rights Outstanding, Measurement Input				5
Underwriter Warrants, September 2019 [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	$ 0.375
Warrants and Rights Outstanding \| $	$ 497,000
Underwriter Warrants, September 2019 [Member] \| Measurement Input, Share Price [Member]
Warrants and Rights Outstanding, Measurement Input	0.36
Underwriter Warrants, September 2019 [Member] \| Measurement Input, Price Volatility [Member]
Warrants and Rights Outstanding, Measurement Input	0.83
Underwriter Warrants, September 2019 [Member] \| Measurement Input, Risk Free Interest Rate [Member]
Warrants and Rights Outstanding, Measurement Input	0.0155
Underwriter Warrants, September 2019 [Member] \| Measurement Input, Expected Dividend Rate [Member]
Warrants and Rights Outstanding, Measurement Input	0
Underwriter Warrants, September 2019 [Member] \| Measurement Input, Expected Term [Member]
Warrants and Rights Outstanding, Measurement Input	5
Second Set of Warrants Expiring September 2024 [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 0.30
Warrant Exercise Price to be Entitled to Receive Cash Consideration, Fundamental Transaction	0.30
Third Set of Warrants Expiring September 2024 [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights	0.375
Warrant Exercise Price to be Entitled to Receive Cash Consideration, Fundamental Transaction	0.375
First Set of Warrants Expiring April 2024 [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights	1.10
Warrant Exercise Price to be Entitled to Receive Cash Consideration, Fundamental Transaction	$ 1.10