Note 8 - Convertible Notes - Convertible Notes (Details) - Convertible Debt [Member] - USD ($)	Mar. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Long-term Debt	$ 6,330,519	$ 6,224,325	$ 5,143,647
Less: current portion	5,492,639	5,185,412	3,597,760
Long-term portion loans payable - related party	837,880	1,038,913	1,545,887
Convertible Notes 1[Member]
Long-term Debt	778,712	850,519	809,755
Convertible Notes 2 [Member]
Long-term Debt	$ 5,551,807	$ 5,373,806	$ 4,333,892

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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