Note 2 - Fair Value of Financial Instruments - Financial Instruments (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021
Reported Value Measurement [Member]
Total	$ 8,152,810	$ 7,914,479
Estimate of Fair Value Measurement [Member]
Total	8,148,126	7,912,705
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Cash and Cash Equivalents Excluding Certificates of Deposit [Member]
Cash and cash equivalents	7,148,207	7,409,873
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Certificates of Deposit [Member]
Cash and cash equivalents	1,004,603	0
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Cash and Cash Equivalents Excluding Certificates of Deposit [Member]
Cash and cash equivalents	7,148,207	7,409,873
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Certificates of Deposit [Member]
Cash and cash equivalents	999,919	0
Fair Value, Inputs, Level 1 [Member] \| Reported Value Measurement [Member]
Equity investment in mutual funds	0	504,606
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member]
Equity investment in mutual funds	$ 0	$ 502,832

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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