Note 10 - Convertible Notes - Related Parties - Convertible Notes Payable to Related Parties (Details) - Convertible Debt Payable to Related Party [Member] - USD ($)	Jun. 30, 2018	Dec. 31, 2017
Long-term Debt	$ 2,710,313	$ 2,710,313
Less current portion	1,098,000	2,210,313
Loans and convertible notes payable, less current portion	1,612,313	500,000
Bill Chaaban, President of Cen Biotech [Member]
Long-term Debt	1,388,122	1,388,122
Director, Harold Aubrey de Lavenu [Member]
Long-term Debt	1,050,000	1,050,000
Director, Alex Tarrabain [Member]
Long-term Debt	48,000	48,000
Joseph Byrne [Member]
Long-term Debt	$ 224,191	$ 224,191

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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