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Note 2 - Securities - Debt Securities by Maturity (Details) - USD ($) | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Due in one year or less, weighted average yield | 2.52% |
Due in one year or less, amortized cost | $ 5,906,000 |
Due in one year or less, fair value | $ 5,939,000 |
Due from one to five years, weighted average yield | 1.16% |
Due from one to five years, amortized cost | $ 93,320,000 |
Due from one to five years, fair value | $ 94,474,000 |
Due from five to ten years, weighted average yield | 1.67% |
Due from five to ten years, amortized cost | $ 176,848,000 |
Due from five to ten years, fair value | $ 180,541,000 |
Due after ten years, weighted average yield | 2.07% |
Due after ten years, amortized cost | $ 79,960,000 |
Due after ten years, fair value | $ 81,003,000 |
Weighted average yield | 1.67% |
Amortized cost | $ 380,403,000 | $ 329,979,000
Fair value | $ 387,347,000 | 334,655,000
Collateralized Mortgage Backed Securities [Member] |  |
No single maturity, weighted average yield | 2.10% |
No single maturity, amortized cost | $ 23,869,000 |
No single maturity, fair value | 24,890,000 |
Amortized cost | 23,869,000 | 41,998,000
Fair value | $ 24,890,000 | 42,470,000
Other Debt and Equity Securities [Member] |  |
No single maturity, weighted average yield | 4.13% |
No single maturity, amortized cost | $ 500,000 |
No single maturity, fair value | 500,000 |
Amortized cost | 500,000 | 500,000
Fair value | $ 500,000 | $ 500,000

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