Note 12 - Convertible Notes - Related Parties - Convertible Notes Payable to Related Parties (Details) - Convertible Debt Payable to Related Party [Member] - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Long-term Debt	$ 2,538,681	$ 2,710,313
Less: current portion	926,368	2,210,313
Long-term portion loans payable - related party	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	878,368	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.

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