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Note 2 - Securities - Credit Quality Indicators for Held to Maturity Securities (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Amortized cost, held to maturity securities |  | $ 106,527 | $ 109,835
Moody's, Aaa Rating [Member] |  |  |
Amortized cost, held to maturity securities |  | 35,530 | 35,292
Moody's, Aa1/Aa2/Aa3 Rating [Member] |  |  |
Amortized cost, held to maturity securities |  | 8,165 | 8,162
Moody's, Baa1/ Baa2/ Baa3 Rating [Member] |  |  |
Amortized cost, held to maturity securities |  | 3,000 | 3,000
Not Rated - Agency [Member] |  |  |
Amortized cost, held to maturity securities | [1] | 59,832 | 63,381
US Treasury Securities [Member] |  |  |
Amortized cost, held to maturity securities |  | 9,759 | 9,632
US Treasury Securities [Member] | Moody's, Aaa Rating [Member] |  |  |
Amortized cost, held to maturity securities |  | 9,759 | 9,632
US Treasury Securities [Member] | Moody's, Aa1/Aa2/Aa3 Rating [Member] |  |  |
Amortized cost, held to maturity securities |  | 0 | 0
US Treasury Securities [Member] | Moody's, Baa1/ Baa2/ Baa3 Rating [Member] |  |  |
Amortized cost, held to maturity securities |  | 0 | 0
US Treasury Securities [Member] | Not Rated - Agency [Member] |  |  |
Amortized cost, held to maturity securities | [1] | 0 | 0
US Agency and Mortgage-backed Securities [Member] |  |  |
Amortized cost, held to maturity securities |  | 83,126 | 86,554
US Agency and Mortgage-backed Securities [Member] | Moody's, Aaa Rating [Member] |  |  |
Amortized cost, held to maturity securities |  | 23,294 | 23,173
US Agency and Mortgage-backed Securities [Member] | Moody's, Aa1/Aa2/Aa3 Rating [Member] |  |  |
Amortized cost, held to maturity securities |  | 0 | 0
US Agency and Mortgage-backed Securities [Member] | Moody's, Baa1/ Baa2/ Baa3 Rating [Member] |  |  |
Amortized cost, held to maturity securities |  | 0 | 0
US Agency and Mortgage-backed Securities [Member] | Not Rated - Agency [Member] |  |  |
Amortized cost, held to maturity securities | [1] | 59,832 | 63,381
US States and Political Subdivisions Debt Securities [Member] |  |  |
Amortized cost, held to maturity securities |  | 10,642 | 10,649
US States and Political Subdivisions Debt Securities [Member] | Moody's, Aaa Rating [Member] |  |  |
Amortized cost, held to maturity securities |  | 2,477 | 2,487
US States and Political Subdivisions Debt Securities [Member] | Moody's, Aa1/Aa2/Aa3 Rating [Member] |  |  |
Amortized cost, held to maturity securities |  | 8,165 | 8,162
US States and Political Subdivisions Debt Securities [Member] | Moody's, Baa1/ Baa2/ Baa3 Rating [Member] |  |  |
Amortized cost, held to maturity securities |  | 0 | 0
US States and Political Subdivisions Debt Securities [Member] | Not Rated - Agency [Member] |  |  |
Amortized cost, held to maturity securities | [1] | 0 | 0
Corporate Debt Securities [Member] |  |  |
Amortized cost, held to maturity securities |  | 3,000 | 3,000
Corporate Debt Securities [Member] | Moody's, Aaa Rating [Member] |  |  |
Amortized cost, held to maturity securities |  | 0 | 0
Corporate Debt Securities [Member] | Moody's, Aa1/Aa2/Aa3 Rating [Member] |  |  |
Amortized cost, held to maturity securities |  | 0 | 0
Corporate Debt Securities [Member] | Moody's, Baa1/ Baa2/ Baa3 Rating [Member] |  |  |
Amortized cost, held to maturity securities |  | 3,000 | 3,000
Corporate Debt Securities [Member] | Not Rated - Agency [Member] |  |  |
Amortized cost, held to maturity securities | [1] | $ 0 | $ 0
[1] | Generally considered not to have credit risk given the implied governmental guarantees associated with these agencies.

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