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Note 2 - Securities Available for Sale - Schedule of Debt Securities Available for Sale (Details) - USD ($) | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Amortized cost | $ 163,334,854 | $ 145,878,693
Gross unrealized gains | 1,892,475 | 543,015
Gross unrealized losses | (4,480,090) | (6,114,261)
Fair value | 160,747,239 | 140,307,447
US Government Agencies Debt Securities [Member] |  |
Amortized cost, one through five years | 3,000,000 | 3,000,000
Gross unrealized gains, one through five years | 0 | 0
Gross unrealized losses, one through five years | (70,821) | (151,590)
Fair value, one through five years | 2,929,179 | 2,848,410
Corporate Debt Securities [Member] |  |
Amortized cost, one through five years | 10,131,978 | 9,112,269
Gross unrealized gains, one through five years | 80,442 | 83,414
Gross unrealized losses, one through five years | (210,021) | (64,547)
Fair value, one through five years | 10,002,399 | 9,131,136
Amortized cost, five through ten years | 30,585,848 | 25,410,219
Gross unrealized gains, five through ten years | 520,032 | 202,205
Gross unrealized losses, five through ten years | (852,504) | (1,389,376)
Fair value, five through ten years | 30,253,376 | 24,223,048
Amortized cost, greater than ten years | 5,849,234 | 4,321,924
Gross unrealized gains, greater than ten years | 225,891 | 202,576
Gross unrealized losses, greater than ten years | 0 | 0
Fair value, greater than ten years | 6,075,125 | 4,524,500
Amortized cost, less than one year |  | 10,000,000
Gross unrealized gains, less than one year |  | 0
Gross unrealized losses, less than one year |  | (55,870)
Fair value, less than one year |  | 9,944,130
US Treasury Bill Securities [Member] |  |
Amortized cost, less than one year |  | 350,000
Gross unrealized gains, less than one year |  | 1,090
Gross unrealized losses, less than one year |  | 0
Fair value, less than one year |  | 351,090
US States and Political Subdivisions Debt Securities [Member] |  |
Amortized cost, five through ten years | 505,933 |
Gross unrealized gains, five through ten years | 0 |
Gross unrealized losses, five through ten years | (81,653) |
Fair value, five through ten years | 424,280 |
Amortized cost, greater than ten years |  | 506,706
Gross unrealized gains, greater than ten years |  | 0
Gross unrealized losses, greater than ten years |  | (108,431)
Fair value, greater than ten years |  | 398,275
Residential Mortgage-Backed Securities [Member] |  |
Amortized cost | 99,876,238 | 76,661,752
Gross unrealized gains | 1,066,110 | 53,730
Gross unrealized losses | (1,611,337) | (2,162,673)
Fair value | 99,331,011 | 74,552,809
Commercial Mortgage-Backed Securities [Member] |  |
Amortized cost | 13,385,623 | 16,515,823
Gross unrealized gains | 0 | 0
Gross unrealized losses | (1,653,754) | (2,181,774)
Fair value | $ 11,731,869 | $ 14,334,049

X
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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2 + Details
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