Note 4 - Loans - Impaired Loans (Details) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Unpaid Contractual Principal Balance	$ 6,970,820	$ 7,012,609
Recorded Investment With No Allowance	6,315,410	6,357,199
Recorded Investment With Allowance	655,410	655,410
Total Recorded Investment	6,970,820	7,012,609
Related Allowance	281,910	281,910
Average Recorded Investment	6,991,715	6,858,745
Interest Recognized	25,432	195,756
Commercial Real Estate Portfolio Segment [Member]
Unpaid Contractual Principal Balance	6,781,030	6,820,932
Recorded Investment With No Allowance	6,278,069	6,317,971
Recorded Investment With Allowance	502,961	502,961
Total Recorded Investment	6,781,030	6,820,932
Related Allowance	129,461	129,461
Average Recorded Investment	6,800,981	6,740,539
Interest Recognized	25,054	125,079
Residential Portfolio Segment [Member]
Unpaid Contractual Principal Balance	37,341	39,228
Recorded Investment With No Allowance	37,341	39,228
Recorded Investment With Allowance	0	0
Total Recorded Investment	37,341	39,228
Related Allowance	0	0
Average Recorded Investment	38,285	41,981
Interest Recognized	0	1,672
Commercial Portfolio Segment [Member]
Unpaid Contractual Principal Balance	152,449	152,449
Recorded Investment With No Allowance	0	0
Recorded Investment With Allowance	152,449	152,449
Total Recorded Investment	152,449	152,449
Related Allowance	152,449	152,449
Average Recorded Investment	152,449	76,225
Interest Recognized	$ 378	$ 69,005

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5258-111524

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953550-111524

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