Note 5 - Common Stock (Details Textual) - shares	Mar. 31, 2020	Dec. 31, 2019
Common Stock, Shares Authorized (in shares)	100,000,000	100,000,000
Common Stock, Shares Outstanding and Reserved (in shares)	49,969,579
Common Stock, Shares, Issued, Total (in shares)	40,516,351	40,516,351
Options [Member]
Common Stock, Capital Shares Reserved for Future Issuance (in shares)	4,657,000
Officer [Member]
Common Stock, Capital Shares Reserved for Future Issuance (in shares)	333,912
Employees [Member]
Common Stock, Capital Shares Reserved for Future Issuance (in shares)	6,309
One of the Investors [Member]
Common Stock, Capital Shares Reserved for Future Issuance (in shares)	400,000
Consultants [Member]
Common Stock, Capital Shares Reserved for Future Issuance (in shares)	73,973
Convertible Debt Securities [Member]
Common Stock, Capital Shares Reserved for Future Issuance (in shares)	3,529,417
Warrant [Member]
Common Stock, Capital Shares Reserved for Future Issuance (in shares)	452,617

Number of shares of common stock outstanding and reserved for issuance.

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Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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