Note 7 - Loans Payable-Related Party - Loans Payable to Related Parties (Details) (Parentheticals)	3 Months Ended	12 Months Ended
Mar. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($) shares	Mar. 31, 2020 CAD ($) shares	Dec. 31, 2019 CAD ($) shares
Director, Alex Tarrabain [Member]
Interest Rate	5.00%	5.00%	5.00%	5.00%
Maturity Date	Mar. 31, 2019	Mar. 31, 2019
Loans Payable to Related Party [Member] \| Bill Chaaban, President of Cen Biotech [Member]
Interest Rate	10.00%	10.00%	10.00%	10.00%
Maturity Date	Dec. 31, 2018	Dec. 31, 2018
Loans Payable to Related Party [Member] \| Bill Chaaban, President of Cen Biotech [Member] \| Loans Payable in Default, One [Member]
Original Amount \| $			$ 48,630	$ 48,630
Loans Payable to Related Party [Member] \| Bill Chaaban, President of Cen Biotech [Member] \| Loans Payable in Default, Two [Member]
Original Amount \| $	$ 198,660	$ 198,660
Loans Payable to Related Party [Member] \| Creative Edge [Member]
Interest Rate	10.00%	10.00%	10.00%	10.00%
Maturity Date	Dec. 31, 2018	Dec. 31, 2018
Loans Payable to Related Party [Member] \| R&D Labs Canada, Inc [Member]
Interest Rate	8.00%	8.00%	8.00%	8.00%
Maturity Date	Oct. 02, 2019	Oct. 02, 2019
Loans Payable to Related Party [Member] \| Spouse of Joseph Byrne, CEO of CEN Biotech [Member]
Interest Rate	5.00%	5.00%	5.00%	5.00%
Maturity Date	Jun. 16, 2020	Jun. 16, 2020
Share Interest (in shares)	4,000	4,000	4,000	4,000
Loans Payable to Related Party [Member] \| Director, Alex Tarrabain [Member]
Maturity Date	Jun. 16, 2020	Jun. 16, 2020
Share Interest (in shares)	3,000	3,000	3,000	3,000
Loans Payable to Related Party [Member] \| Joseph Byrne [Member]
Interest Rate	5.00%	5.00%	5.00%	5.00%
Maturity Date	Jun. 16, 2020	Jun. 16, 2020
Share Interest (in shares)	2,000	2,000	2,000	2,000

Contractual share interest, per 30-day period, for funds borrowed under the debt agreement.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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- Definition

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

+ 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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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
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-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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