Note 8 - Commitments (Details Textual)	3 Months Ended	12 Months Ended
Mar. 31, 2020 USD ($) ft²	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($) ft²	Dec. 31, 2018 USD ($)
Area of Real Estate Property (Square Foot) \| ft²	8,400		8,400
Operating Leases, Rent Expense, Total	$ 41,539	$ 40,316	$ 161,673	$ 156,939
Lessee, Operating Lease, Liability, to be Paid, Remainder of Fiscal Year	124,616
Lessee, Operating Lease, Liability, Payments, Due Year Two	171,213		171,213
Lessee, Operating Lease, Liability, Payments, Due Year Three	176,356		176,356
Unrecorded Unconditional Purchase Obligation, Total	$ 539,000		$ 294,000

Area of a real estate property.

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- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease having initial or remaining lease term in excess of one year to be paid in remainder of current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

+ Details

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- Definition

Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121559207&loc=d3e25336-109308

+ Details

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