Note 10 - Convertible Notes - Related Parties - Convertible Notes Payable to Related Parties (Details) (Parentheticals)	3 Months Ended	12 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Director, Alex Tarrabain [Member]
Maturing Dates	Jun. 15, 2018
Joseph Byrne [Member]
Maturing Dates	Jun. 15, 2018
Convertible Debt Payable to Related Party [Member]
Conversion Rights	1,693,946
Convertible Debt Payable to Related Party [Member] \| Bill Chaaban, President of Cen Biotech [Member]
Interest Rate	12.00%	12.00%
Conversion Rights	867,576	867,576
Maturing Dates	Dec. 31, 2018	Dec. 31, 2018
Convertible Debt Payable to Related Party [Member] \| Director, Harold Aubrey de Lavenu [Member]
Interest Rate	5.00%	5.00%
Conversion Rights	656,250	656,250
Maturing Dates	Between July 2018 and Feb 2019	Between July 2018 and Feb 2019
Convertible Debt Payable to Related Party [Member] \| Director, Alex Tarrabain [Member]
Interest Rate	5.00%	5.00%
Conversion Rights	30,000	30,000
Maturing Dates	Oct. 26, 201	Oct. 26, 201
Convertible Debt Payable to Related Party [Member] \| Joseph Byrne [Member]
Interest Rate	12.00%	12.00%
Conversion Rights	140,120	140,120
Maturing Dates	Aug. 17, 2018	Aug. 17, 2018

The maturity various date range of a debt instrument.

No definition available.

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- Definition

The number of equity instruments that the holder of the debt instrument would receive if the debt was converted to equity.

+ References

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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-Publisher FASB
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-Topic 210
-SubTopic 10
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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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