Note 13 - Financial Instruments - Recurring Fair Value Measurements (Details) - USD ($)	Jun. 30, 2022	Dec. 31, 2021
Interest rate swap contracts, current portion	$ 984,547	$ 540,753
Interest rate swap contracts, long-term portion	0	952,666
Interest rate swap contracts, noncurrent portion	1,014,196	0
Fair Value, Recurring [Member]
Interest rate swap contracts, current portion	984,547	540,753
Interest rate swap contracts, long-term portion		952,666
Interest rate swap contracts, noncurrent portion	1,014,196
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Interest rate swap contracts, current portion		0
Interest rate swap contracts, long-term portion		0
Interest rate swap contracts, noncurrent portion	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Interest rate swap contracts, current portion	984,547	540,753
Interest rate swap contracts, long-term portion		952,666
Interest rate swap contracts, noncurrent portion	1,014,196
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Interest rate swap contracts, current portion	0	0
Interest rate swap contracts, long-term portion		$ 0
Interest rate swap contracts, noncurrent portion	$ 0

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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