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Note 3 - Securities - Debt Securities by Maturity (Details) - USD ($) | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Due in one year or less, weighted average yield | 2.04% |
Due in one year or less, amortized cost | $ 14,118,000 |
Due in one year or less, fair value | $ 14,136,000 |
Due from one to five years, weighted average yield | 2.36% |
Due from one to five years, amortized cost | $ 52,865,000 |
Due from one to five years, fair value | $ 53,389,000 |
Due from five to ten years, weighted average yield | 2.66% |
Due from five to ten years, amortized cost | $ 105,156,000 |
Due from five to ten years, fair value | $ 106,960,000 |
Due after ten years, weighted average yield | 3.09% |
Due after ten years, amortized cost | $ 115,342,000 |
Due after ten years, fair value | $ 117,200,000 |
Weighted average yield | 2.76% |
Amortized cost | $ 329,979,000 | $ 347,795,000
Fair value | $ 334,655,000 | 337,366,000
Collateralized Mortgage Backed Securities [Member] |  |
No single maturity, weighted average yield | 2.76% |
No single maturity, amortized cost | $ 41,998,000 |
No single maturity, fair value | 42,470,000 |
Amortized cost | 41,998,000 | 44,263,000
Fair value | $ 42,470,000 | 43,658,000
Other Debt and Equity Securities [Member] |  |
No single maturity, weighted average yield | 5.88% |
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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