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Note 2 - Securities - Investments in an Unrealized Loss Position That Were Temporarily Impaired (Details) - USD ($) $ in Thousands | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Less than 12 months, fair value, available for sale securities | $ 3,601 | $ 5,750
Less than 12 months, unrealized (loss), available for sale securities | (143) | (244)
12 months or more, fair value, available for sale securities | 133,391 | 137,254
12 months or more, unrealized (loss), available for sale securities | (17,165) | (20,418)
Total, fair value, available for sale securities | 136,992 | 143,004
Total, unrealized (loss), available for sale securities | (17,308) | (20,662)
US Treasury Securities [Member] |  |
Less than 12 months, fair value, available for sale securities | 0 | 0
Less than 12 months, unrealized (loss), available for sale securities | 0 | 0
12 months or more, fair value, available for sale securities | 11,829 | 11,450
12 months or more, unrealized (loss), available for sale securities | (652) | (1,026)
Total, fair value, available for sale securities | 11,829 | 11,450
Total, unrealized (loss), available for sale securities | (652) | (1,026)
US Agency and Mortgage-backed Securities [Member] |  |
Less than 12 months, fair value, available for sale securities | 617 | 1,281
Less than 12 months, unrealized (loss), available for sale securities | (5) | (29)
12 months or more, fair value, available for sale securities | 73,033 | 78,800
12 months or more, unrealized (loss), available for sale securities | (9,636) | (12,163)
Total, fair value, available for sale securities | 73,650 | 80,081
Total, unrealized (loss), available for sale securities | (9,641) | (12,192)
US States and Political Subdivisions Debt Securities [Member] |  |
Less than 12 months, fair value, available for sale securities | 2,984 | 4,469
Less than 12 months, unrealized (loss), available for sale securities | (138) | (215)
12 months or more, fair value, available for sale securities | 48,529 | 47,004
12 months or more, unrealized (loss), available for sale securities | (6,877) | (7,229)
Total, fair value, available for sale securities | 51,513 | 51,473
Total, unrealized (loss), available for sale securities | $ (7,015) | $ (7,444)

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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 55 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479081/326-30-55-8 Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-7 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479106/326-30-50-5 + Details
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