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Note 5 - Fair Value Measurements - Estimated Fair Value of the Company's Financial Instruments (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Reported Value Measurement [Member] |  |
Financial assets: |  |
Net loans | $ 1,583,995 | $ 1,497,167
Mortgage servicing rights | 1,423 | 1,497
Financial liabilities: |  |
Non-maturing deposits | 1,351,857 | 1,197,989
Time deposits | 270,445 | 247,704
Other borrowings | 11,502 | 11,660
Estimate of Fair Value Measurement [Member] |  |
Financial assets: |  |
Net loans | 1,572,635 | 1,462,650
Mortgage servicing rights | 2,398 | 2,522
Financial liabilities: |  |
Non-maturing deposits | 1,351,857 | 1,197,989
Time deposits | 269,408 | 245,999
Other borrowings | 11,502 | 11,660
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Financial assets: |  |
Net loans | 0 | 0
Mortgage servicing rights | 0 | 0
Financial liabilities: |  |
Non-maturing deposits | 1,351,857 | 1,197,989
Time deposits | 0 | 0
Other borrowings | 0 | 0
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Financial assets: |  |
Net loans | 0 | 0
Mortgage servicing rights | 0 | 0
Financial liabilities: |  |
Non-maturing deposits | 0 | 0
Time deposits | 0 | 0
Other borrowings | 0 | 0
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Financial assets: |  |
Net loans | 1,572,635 | 1,462,650
Mortgage servicing rights | 2,398 | 2,522
Financial liabilities: |  |
Non-maturing deposits | 0 | 0
Time deposits | 269,408 | 245,999
Other borrowings | $ 11,502 | $ 11,660

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- Definition Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Name Accounting Standards Codification -Section 55 -Paragraph 10 -SubTopic 10 -Topic 825 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482881/825-10-55-10 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 28 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-28 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-11 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-11 Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-10 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482881/825-10-55-12 + Details
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