v3.26.1
Note 5 - Loans and the Allowance for Credit Losses - Loan Portfolio Allocated by Internal Risk Ratings (Details) - USD ($)
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Loans, Year One $ 179,376,000 $ 141,749,000  
Loans, Year Two 177,177,000 158,667,000  
Loans, Year Three 202,401,000 206,399,000  
Loans, Year Four 247,434,000 123,605,000  
Loans, Year Five 182,046,000 100,390,000  
Loans, Prior 388,649,000 208,524,000  
Loans, Revolving 136,152,000 75,475,000  
Loans, Revolving Converted to Term 2,558,000 3,762,000  
Loans, Total 1,515,793,000 1,018,571,000  
Loans, Year One, Write-offs 0 0  
Loans, Year Two, Write-offs 153,000 484,000  
Loans, Year Three, Write-offs 164,000 676,000  
Loans, Year Four, Write-offs 311,000 293,000  
Loans, Year Five, Write-offs 43,000 177,000  
Loans, Prior, Write-offs 168,000 257,000  
Loans, Revolving, Write-offs 256,000 152,000  
Loans, Total, Write-offs 1,095,000 2,039,000  
Loans, Revolving Converted to Term, Write-offs 0 0  
Performing Financial Instruments [Member]      
Loans, Year One 5,854,000 2,433,000  
Loans, Year Two 6,203,000 24,408,000  
Loans, Year Three 17,904,000 23,160,000  
Loans, Year Four 17,539,000 10,744,000  
Loans, Year Five 5,735,000 4,867,000  
Loans, Prior 3,185,000 4,068,000  
Loans, Revolving 440,000 157,000  
Loans, Revolving Converted to Term 0 0  
Loans, Total 56,860,000 69,837,000  
Nonperforming Financial Instruments [Member]      
Loans, Year One 0 0  
Loans, Year Two 21,000 195,000  
Loans, Year Three 191,000 265,000  
Loans, Year Four 159,000 190,000  
Loans, Year Five 233,000 131,000  
Loans, Prior 163,000 88,000  
Loans, Revolving 0 2,000  
Loans, Revolving Converted to Term 0 0  
Loans, Total 767,000 871,000  
Commercial Portfolio Segment [Member] | Commercial Loans [Member]      
Loans, Year One 23,879,000 19,946,000  
Loans, Year Two 30,424,000 12,886,000  
Loans, Year Three 22,487,000 13,249,000  
Loans, Year Four 25,952,000 9,214,000  
Loans, Year Five 12,690,000 2,127,000  
Loans, Prior 13,489,000 6,952,000  
Loans, Revolving 39,775,000 13,820,000  
Loans, Revolving Converted to Term 0 0  
Loans, Total 168,696,000 78,194,000  
Loans, Year One, Write-offs 0 0  
Loans, Year Two, Write-offs 114,000 86,000  
Loans, Year Three, Write-offs 0 43,000  
Loans, Year Four, Write-offs 51,000 0  
Loans, Year Five, Write-offs 0 0  
Loans, Prior, Write-offs 0 22,000  
Loans, Revolving, Write-offs 190,000 151,000  
Loans, Total, Write-offs 355,000 302,000 $ 123,000
Loans, Revolving Converted to Term, Write-offs   0  
Commercial Portfolio Segment [Member] | Commercial Loans [Member] | Pass [Member]      
Loans, Year One 23,877,000 19,885,000  
Loans, Year Two 30,424,000 12,642,000  
Loans, Year Three 22,262,000 12,042,000  
Loans, Year Four 25,867,000 8,405,000  
Loans, Year Five 11,871,000 1,658,000  
Loans, Prior 13,150,000 6,886,000  
Loans, Revolving 39,108,000 13,232,000  
Loans, Revolving Converted to Term 0 0  
Loans, Total 166,559,000 74,750,000  
Commercial Portfolio Segment [Member] | Commercial Loans [Member] | Special Mention [Member]      
Loans, Year One 0 0  
Loans, Year Two 0 0  
Loans, Year Three 0 157,000  
Loans, Year Four 0 444,000  
Loans, Year Five 65,000 0  
Loans, Prior 0 36,000  
Loans, Revolving 473,000 513,000  
Loans, Revolving Converted to Term 0 0  
Loans, Total 538,000 1,150,000  
Commercial Portfolio Segment [Member] | Commercial Loans [Member] | Substandard [Member]      
Loans, Year One 2,000 61,000  
Loans, Year Two 0 244,000  
Loans, Year Three 225,000 1,050,000  
Loans, Year Four 85,000 365,000  
Loans, Year Five 754,000 469,000  
Loans, Prior 339,000 30,000  
Loans, Revolving 194,000 75,000  
Loans, Revolving Converted to Term 0 0  
Loans, Total 1,599,000 2,294,000  
Commercial Portfolio Segment [Member] | Agricultural Loans [Member]      
Loans, Year One 10,495,000 6,939,000  
Loans, Year Two 7,124,000 12,094,000  
Loans, Year Three 20,653,000 20,055,000  
Loans, Year Four 24,101,000 14,999,000  
Loans, Year Five 17,659,000 15,637,000  
Loans, Prior 41,539,000 30,995,000  
Loans, Revolving 36,197,000 18,391,000  
Loans, Revolving Converted to Term 0 0  
Loans, Total 157,768,000 119,110,000  
Loans, Year One, Write-offs 0 0  
Loans, Year Two, Write-offs 0 0  
Loans, Year Three, Write-offs 11,000 0  
Loans, Year Four, Write-offs 0 0  
Loans, Year Five, Write-offs 0 0  
Loans, Prior, Write-offs 0 0  
Loans, Revolving, Write-offs 0 0  
Loans, Total, Write-offs 11,000 0 (0)
Loans, Revolving Converted to Term, Write-offs 0 0  
Commercial Portfolio Segment [Member] | Agricultural Loans [Member] | Pass [Member]      
Loans, Year One 9,045,000 6,421,000  
Loans, Year Two 6,893,000 9,331,000  
Loans, Year Three 15,988,000 14,290,000  
Loans, Year Four 11,829,000 11,389,000  
Loans, Year Five 13,875,000 14,252,000  
Loans, Prior 35,349,000 28,075,000  
Loans, Revolving 32,117,000 13,356,000  
Loans, Revolving Converted to Term 0 0  
Loans, Total 125,096,000 97,114,000  
Commercial Portfolio Segment [Member] | Agricultural Loans [Member] | Special Mention [Member]      
Loans, Year One 285,000 518,000  
Loans, Year Two 0 53,000  
Loans, Year Three 419,000 1,159,000  
Loans, Year Four 1,036,000 358,000  
Loans, Year Five 806,000 1,307,000  
Loans, Prior 4,867,000 1,639,000  
Loans, Revolving 3,365,000 534,000  
Loans, Revolving Converted to Term 0 0  
Loans, Total 10,778,000 5,568,000  
Commercial Portfolio Segment [Member] | Agricultural Loans [Member] | Substandard [Member]      
Loans, Year One 1,165,000 0  
Loans, Year Two 231,000 2,710,000  
Loans, Year Three 4,246,000 4,606,000  
Loans, Year Four 11,236,000 3,252,000  
Loans, Year Five 2,978,000 78,000  
Loans, Prior 1,323,000 1,281,000  
Loans, Revolving 715,000 4,501,000  
Loans, Revolving Converted to Term 0 0  
Loans, Total 21,894,000 16,428,000  
Commercial Portfolio Segment [Member] | Real Estate Loan [Member]      
Loans, Year One 127,339,000 90,579,000  
Loans, Year Two 116,542,000 92,735,000  
Loans, Year Three 128,720,000 138,406,000  
Loans, Year Four 166,852,000 82,627,000  
Loans, Year Five 138,277,000 74,326,000  
Loans, Prior 319,846,000 160,686,000  
Loans, Revolving 6,368,000 7,592,000  
Loans, Revolving Converted to Term 0 0  
Loans, Total 1,003,944,000 646,951,000  
Loans, Year One, Write-offs 0 0  
Loans, Year Two, Write-offs 0 0  
Loans, Year Three, Write-offs 0 0  
Loans, Year Four, Write-offs 0 0  
Loans, Year Five, Write-offs 0 0  
Loans, Prior, Write-offs 0 0  
Loans, Revolving, Write-offs 0 0  
Loans, Total, Write-offs 0 0 (0)
Loans, Revolving Converted to Term, Write-offs 0 0  
Commercial Portfolio Segment [Member] | Real Estate Loan [Member] | Pass [Member]      
Loans, Year One 126,156,000 90,579,000  
Loans, Year Two 116,542,000 92,735,000  
Loans, Year Three 128,720,000 137,607,000  
Loans, Year Four 166,246,000 82,627,000  
Loans, Year Five 136,927,000 73,405,000  
Loans, Prior 309,406,000 154,466,000  
Loans, Revolving 6,368,000 7,142,000  
Loans, Revolving Converted to Term 0 0  
Loans, Total 990,365,000 638,561,000  
Commercial Portfolio Segment [Member] | Real Estate Loan [Member] | Special Mention [Member]      
Loans, Year One 1,183,000 0  
Loans, Year Two 0 0  
Loans, Year Three 0 210,000  
Loans, Year Four 238,000 0  
Loans, Year Five 941,000 0  
Loans, Prior 1,756,000 0  
Loans, Revolving 0 0  
Loans, Revolving Converted to Term 0 0  
Loans, Total 4,118,000 210,000  
Commercial Portfolio Segment [Member] | Real Estate Loan [Member] | Substandard [Member]      
Loans, Year One 0 0  
Loans, Year Two 0 0  
Loans, Year Three 0 628,000  
Loans, Year Four 368,000 0  
Loans, Year Five 409,000 921,000  
Loans, Prior 8,684,000 1,760,000  
Loans, Revolving 0 0  
Loans, Revolving Converted to Term 0 0  
Loans, Total 9,461,000 3,309,000  
Commercial Portfolio Segment [Member] | Construction Loans [Member]      
Loans, Year One 9,175,000 21,220,000  
Loans, Year Two 12,674,000 15,244,000  
Loans, Year Three 10,636,000 11,264,000  
Loans, Year Four 3,516,000 3,767,000  
Loans, Year Five 1,627,000 947,000  
Loans, Prior 1,069,000 843,000  
Loans, Revolving 1,325,000 0  
Loans, Revolving Converted to Term 0 0  
Loans, Total 40,022,000 53,285,000  
Loans, Year One, Write-offs 0 0  
Loans, Year Two, Write-offs 0 0  
Loans, Year Three, Write-offs 0 0  
Loans, Year Four, Write-offs 0 0  
Loans, Year Five, Write-offs 0 0  
Loans, Prior, Write-offs 0 0  
Loans, Revolving, Write-offs 0 0  
Loans, Total, Write-offs 0 0 (0)
Loans, Revolving Converted to Term, Write-offs 0 0  
Commercial Portfolio Segment [Member] | Construction Loans [Member] | Pass [Member]      
Loans, Year One 9,175,000 21,110,000  
Loans, Year Two 12,674,000 15,244,000  
Loans, Year Three 6,240,000 11,054,000  
Loans, Year Four 3,516,000 3,767,000  
Loans, Year Five 1,627,000 947,000  
Loans, Prior 1,069,000 843,000  
Loans, Revolving 1,325,000 0  
Loans, Revolving Converted to Term 0 0  
Loans, Total 35,626,000 52,965,000  
Commercial Portfolio Segment [Member] | Construction Loans [Member] | Special Mention [Member]      
Loans, Year One 0    
Loans, Year Two 0    
Loans, Year Three 4,396,000    
Loans, Year Four 0    
Loans, Year Five 0    
Loans, Prior 0    
Loans, Revolving 0    
Loans, Revolving Converted to Term 0    
Loans, Total 4,396,000    
Residential Portfolio Segment [Member] | Real Estate Loan [Member]      
Loans, Year One 2,634,000 632,000  
Loans, Year Two 4,189,000 1,105,000  
Loans, Year Three 1,810,000 0  
Loans, Year Four 9,315,000 2,064,000  
Loans, Year Five 5,825,000 2,355,000  
Loans, Prior 9,358,000 4,892,000  
Loans, Revolving 11,000 520,000  
Loans, Revolving Converted to Term 0 0  
Loans, Total 33,142,000 11,568,000  
Loans, Year One, Write-offs 0 0  
Loans, Year Two, Write-offs 0 0  
Loans, Year Three, Write-offs 0 0  
Loans, Year Four, Write-offs 0 0  
Loans, Year Five, Write-offs 0 0  
Loans, Prior, Write-offs 0 0  
Loans, Revolving, Write-offs 0 0  
Loans, Total, Write-offs 0 0 (0)
Loans, Revolving Converted to Term, Write-offs 0 0  
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Pass [Member]      
Loans, Year One 2,634,000 632,000  
Loans, Year Two 4,189,000 1,105,000  
Loans, Year Three 1,810,000 0  
Loans, Year Four 9,315,000 2,064,000  
Loans, Year Five 5,825,000 2,355,000  
Loans, Prior 8,980,000 4,639,000  
Loans, Revolving 11,000 520,000  
Loans, Revolving Converted to Term 0 0  
Loans, Total 32,764,000 11,315,000  
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Special Mention [Member]      
Loans, Year One 0 0  
Loans, Year Two 0 0  
Loans, Year Three 0 171,000  
Loans, Year Four 0 0  
Loans, Year Five 0 0  
Loans, Prior 149,000 4,460,000  
Loans, Revolving 450,000  
Loans, Revolving Converted to Term 0  
Loans, Total 149,000 5,081,000  
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Substandard [Member]      
Loans, Year One 0 0  
Loans, Year Two 0 0  
Loans, Year Three 0 0  
Loans, Year Four 0 0  
Loans, Year Five 0 0  
Loans, Prior 229,000 253,000  
Loans, Revolving 0 0  
Loans, Revolving Converted to Term 0 0  
Loans, Total 229,000 253,000  
Residential Portfolio Segment [Member] | Construction Loans [Member] | Substandard [Member]      
Loans, Year One   110,000  
Loans, Year Two   0  
Loans, Year Three   0  
Loans, Year Four   0  
Loans, Year Five   0  
Loans, Prior   0  
Loans, Revolving   0  
Loans, Revolving Converted to Term   0  
Loans, Total   110,000  
Residential Portfolio Segment [Member] | Equity Lines of Credit [Member]      
Loans, Year One 0 0  
Loans, Year Two 0 0  
Loans, Year Three 0 0  
Loans, Year Four 0 0  
Loans, Year Five 0 0  
Loans, Prior 0 0  
Loans, Revolving 52,036,000 34,993,000  
Loans, Revolving Converted to Term 2,558,000 3,762,000  
Loans, Total 54,594,000 38,755,000  
Loans, Year One, Write-offs 0 0  
Loans, Year Two, Write-offs 0 0  
Loans, Year Three, Write-offs 0 0  
Loans, Year Four, Write-offs 0 0  
Loans, Year Five, Write-offs 0 0  
Loans, Prior, Write-offs 0 0  
Loans, Revolving, Write-offs 66,000 0  
Loans, Total, Write-offs 66,000 0 (0)
Loans, Revolving Converted to Term, Write-offs 0 0  
Residential Portfolio Segment [Member] | Equity Lines of Credit [Member] | Pass [Member]      
Loans, Year One 0 0  
Loans, Year Two 0 0  
Loans, Year Three 0 0  
Loans, Year Four 0 0  
Loans, Year Five 0 0  
Loans, Prior  
Loans, Revolving 51,149,000 34,622,000  
Loans, Revolving Converted to Term 2,365,000 3,483,000  
Loans, Total 53,514,000 38,105,000  
Residential Portfolio Segment [Member] | Equity Lines of Credit [Member] | Special Mention [Member]      
Loans, Year One 0    
Loans, Year Two 0    
Loans, Year Three 0    
Loans, Year Four 0    
Loans, Year Five 0    
Loans, Prior 0    
Loans, Revolving 0    
Loans, Revolving Converted to Term 93,000    
Loans, Total 93,000    
Residential Portfolio Segment [Member] | Equity Lines of Credit [Member] | Substandard [Member]      
Loans, Year One 0 0  
Loans, Year Two 0 0  
Loans, Year Three 0 0  
Loans, Year Four 0 0  
Loans, Year Five 0 0  
Loans, Prior  
Loans, Revolving 887,000 371,000  
Loans, Revolving Converted to Term 100,000 279,000  
Loans, Total 987,000 650,000  
Commercial and Residential Portfolio Segments [Member]      
Loans, Year One 173,522,000 139,316,000  
Loans, Year Two 170,953,000 134,064,000  
Loans, Year Three 184,306,000 182,974,000  
Loans, Year Four 229,736,000 112,671,000  
Loans, Year Five 176,078,000 95,392,000  
Loans, Prior 385,301,000 204,368,000  
Loans, Revolving 135,712,000 75,316,000  
Loans, Revolving Converted to Term 2,558,000 3,762,000  
Loans, Total 1,458,166,000 947,863,000  
Loans, Year One, Write-offs 0 0  
Loans, Year Two, Write-offs 114,000 86,000  
Loans, Year Three, Write-offs 11,000 43,000  
Loans, Year Four, Write-offs 51,000 0  
Loans, Year Five, Write-offs 0 0  
Loans, Prior, Write-offs 0 22,000  
Loans, Revolving, Write-offs 256,000 151,000  
Loans, Total, Write-offs 432,000 302,000  
Loans, Revolving Converted to Term, Write-offs 0 0  
Commercial and Residential Portfolio Segments [Member] | Pass [Member]      
Loans, Year One 170,887,000 138,627,000  
Loans, Year Two 170,722,000 131,057,000  
Loans, Year Three 175,020,000 174,993,000  
Loans, Year Four 216,773,000 108,252,000  
Loans, Year Five 170,125,000 92,617,000  
Loans, Prior 367,954,000 194,909,000  
Loans, Revolving 130,078,000 68,872,000  
Loans, Revolving Converted to Term 2,365,000 3,483,000  
Loans, Total 1,403,924,000 912,810,000  
Commercial and Residential Portfolio Segments [Member] | Special Mention [Member]      
Loans, Year One 1,468,000 518,000  
Loans, Year Two 0 53,000  
Loans, Year Three 4,815,000 1,697,000  
Loans, Year Four 1,274,000 802,000  
Loans, Year Five 1,812,000 1,307,000  
Loans, Prior 6,772,000 6,135,000  
Loans, Revolving 3,838,000 1,497,000  
Loans, Revolving Converted to Term 93,000 0  
Loans, Total 20,072,000 12,009,000  
Commercial and Residential Portfolio Segments [Member] | Substandard [Member]      
Loans, Year One 1,167,000 171,000  
Loans, Year Two 231,000 2,954,000  
Loans, Year Three 4,471,000 6,284,000  
Loans, Year Four 11,689,000 3,617,000  
Loans, Year Five 4,141,000 1,468,000  
Loans, Prior 10,575,000 3,324,000  
Loans, Revolving 1,796,000 4,947,000  
Loans, Revolving Converted to Term 100,000 279,000  
Loans, Total 34,170,000 23,044,000  
Consumer Portfolio Segment [Member]      
Loans, Year One 5,854,000 2,433,000  
Loans, Year Two 6,224,000 24,603,000  
Loans, Year Three 18,095,000 23,425,000  
Loans, Year Four 17,698,000 10,934,000  
Loans, Year Five 5,968,000 4,998,000  
Loans, Prior 3,348,000 4,156,000  
Loans, Revolving 440,000 159,000  
Loans, Revolving Converted to Term 0 0  
Loans, Total 57,627,000 70,708,000  
Consumer Portfolio Segment [Member] | Automobile Loan [Member]      
Loans, Year One 0 0  
Loans, Year Two 0 23,310,000  
Loans, Year Three 16,114,000 22,602,000  
Loans, Year Four 14,736,000 10,613,000  
Loans, Year Five 5,846,000 4,908,000  
Loans, Prior 3,324,000 4,151,000  
Loans, Revolving 0 0  
Loans, Revolving Converted to Term 0 0  
Loans, Total 40,020,000 65,584,000  
Loans, Year One, Write-offs 0 0  
Loans, Year Two, Write-offs 0 389,000  
Loans, Year Three, Write-offs 107,000 598,000  
Loans, Year Four, Write-offs 219,000 262,000  
Loans, Year Five, Write-offs 41,000 171,000  
Loans, Prior, Write-offs 161,000 223,000  
Loans, Revolving, Write-offs 0 0  
Loans, Total, Write-offs 528,000 1,643,000 1,550,000
Loans, Revolving Converted to Term, Write-offs 0 0  
Consumer Portfolio Segment [Member] | Automobile Loan [Member] | Performing Financial Instruments [Member]      
Loans, Year One 0 0  
Loans, Year Two 0 23,163,000  
Loans, Year Three 15,923,000 22,361,000  
Loans, Year Four 14,577,000 10,426,000  
Loans, Year Five 5,613,000 4,779,000  
Loans, Prior 3,161,000 4,063,000  
Loans, Revolving 0 0  
Loans, Revolving Converted to Term 0 0  
Loans, Total 39,274,000 64,792,000  
Consumer Portfolio Segment [Member] | Automobile Loan [Member] | Nonperforming Financial Instruments [Member]      
Loans, Year One 0 0  
Loans, Year Two 0 147,000  
Loans, Year Three 191,000 241,000  
Loans, Year Four 159,000 187,000  
Loans, Year Five 233,000 129,000  
Loans, Prior 163,000 88,000  
Loans, Revolving 0 0  
Loans, Revolving Converted to Term 0 0  
Loans, Total 746,000 792,000  
Consumer Portfolio Segment [Member] | Other Loans [Member]      
Loans, Year One 5,854,000 2,433,000  
Loans, Year Two 6,224,000 1,293,000  
Loans, Year Three 1,981,000 823,000  
Loans, Year Four 2,962,000 321,000  
Loans, Year Five 122,000 90,000  
Loans, Prior 24,000 5,000  
Loans, Revolving 440,000 159,000  
Loans, Revolving Converted to Term 0 0  
Loans, Total 17,607,000 5,124,000  
Loans, Year One, Write-offs 0 0  
Loans, Year Two, Write-offs 39,000 9,000  
Loans, Year Three, Write-offs 46,000 35,000  
Loans, Year Four, Write-offs 41,000 31,000  
Loans, Year Five, Write-offs 2,000 6,000  
Loans, Prior, Write-offs 7,000 12,000  
Loans, Revolving, Write-offs 0 1,000  
Loans, Total, Write-offs 135,000 94,000 $ 129,000
Loans, Revolving Converted to Term, Write-offs 0 0  
Consumer Portfolio Segment [Member] | Other Loans [Member] | Performing Financial Instruments [Member]      
Loans, Year One 5,854,000 2,433,000  
Loans, Year Two 6,203,000 1,245,000  
Loans, Year Three 1,981,000 799,000  
Loans, Year Four 2,962,000 318,000  
Loans, Year Five 122,000 88,000  
Loans, Prior 24,000 5,000  
Loans, Revolving 440,000 157,000  
Loans, Revolving Converted to Term 0 0  
Loans, Total 17,586,000 5,045,000  
Consumer Portfolio Segment [Member] | Other Loans [Member] | Nonperforming Financial Instruments [Member]      
Loans, Year One 0 0  
Loans, Year Two 21,000 48,000  
Loans, Year Three 0 24,000  
Loans, Year Four 0 3,000  
Loans, Year Five 0 2,000  
Loans, Prior 0 0  
Loans, Revolving 0 2,000  
Loans, Revolving Converted to Term 0 0  
Loans, Total $ 21,000 $ 79,000