Note 4 - Loans - Non-accrual Loans (Details) - USD ($)	Mar. 31, 2022	Dec. 31, 2021
Nonaccrual loans	$ 4,964,914	$ 4,994,914
Commercial Real Estate Portfolio Segment [Member]
Nonaccrual loans	4,780,965	4,810,965
Residential Portfolio Segment [Member]
Nonaccrual loans	31,500	31,500
Commercial Portfolio Segment [Member]
Nonaccrual loans	$ 152,449	$ 152,449

Amortized cost of financing receivable on nonaccrual status. Excludes net investment in lease.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5111-111524

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (3)

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (2)

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Balance Type:	debit
Period Type:	instant