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Note 4 - Loans and Allowance for Credit Losses - Schedule of Total Loans Outstanding by Portfolio Segment (Details) - USD ($) $ in Thousands | Jun. 30, 2026 | Mar. 31, 2026 | Dec. 31, 2025 | Jun. 30, 2025 | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | --- | --- | --- | --- | ---
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | $ 1,106,100 |  | $ 1,064,259 |  |  |
Allowance for credit losses | (14,795) | $ (14,803) | (14,519) | $ (16,122) | $ (16,535) | $ (15,885)
Deferred origination fees and costs, net | 793 |  | 733 |  |  |
Loans, net | 1,092,098 |  | 1,050,473 |  |  |
Commercial Portfolio Segment [Member] |  |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | 214,185 |  | 146,178 |  |  |
Allowance for credit losses | (2,670) | (2,608) | (2,425) | (2,523) | (2,064) | (1,622)
Commercial Real Estate Portfolio Segment [Member] |  |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | 688,569 |  | 702,455 |  |  |
Allowance for credit losses | (9,122) | (9,185) | (9,343) | (9,782) | (8,871) | (10,245)
Agricultural Portfolio Segment [Member] |  |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | 86,474 |  | 93,627 |  |  |
Allowance for credit losses | (1,120) | (1,149) | (1,074) | (1,983) | (3,932) | (1,555)
Residential Mortgage [Member] |  |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | 98,448 |  | 100,684 |  |  |
Allowance for credit losses | (1,220) | (1,212) | (1,005) | (1,038) | (980) | (1,779)
Residential Portfolio Segment [Member] |  |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | 4,292 |  | 5,837 |  |  |
Allowance for credit losses | (353) | (364) | (376) | (499) | (407) | (433)
Consumer Portfolio Segment [Member] |  |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | 14,132 |  | 15,478 |  |  |
Allowance for credit losses | $ (310) | $ (285) | $ (296) | $ (297) | $ (281) | $ (251)

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- Definition Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477657/942-210-S45-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478478/942-210-S50-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(7)(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 + Details
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