Note 8 - Loans Payable - Related Party - Loans Payable to Related Parties (Details) (Parentheticals) - shares	6 Months Ended	12 Months Ended
Jun. 30, 2019	Dec. 31, 2018
Bill Chaaban, President of Cen Biotech [Member] \| Loans Payable to Related Party [Member]
Interest Rate	10.00%	10.00%
Maturity Date	Dec. 31, 2018	Dec. 31, 2018
Creative Edge [Member] \| Loans Payable to Related Party [Member]
Interest Rate	10.00%	10.00%
Maturity Date	Dec. 31, 2018	Dec. 31, 2018
R&D Labs Canada, Inc [Member] \| Loans Payable to Related Party [Member]
Interest Rate	8.00%	8.00%
Maturity Date	Oct. 02, 2019	Oct. 02, 2019
Spouse of Joseph Byrne, CEO of CEN Biotech [Member] \| Loans Payable to Related Party [Member]
Maturity Date	Jul. 16, 2019	Jul. 16, 2019
Share Interest (in shares)	4,000	4,000
Director, Alex Tarrabain [Member]
Interest Rate		5.00%
Maturity Date		Mar. 31, 2019
Director, Alex Tarrabain [Member] \| Loans Payable to Related Party [Member]
Maturity Date	Jul. 16, 2019	Jul. 16, 2019
Share Interest (in shares)	3,000	3,000
Joseph Byrne [Member] \| Loans Payable to Related Party [Member]
Maturity Date	Jul. 16, 2019	Jul. 16, 2019
Share Interest (in shares)	2,000	2,000

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

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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
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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