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Note 2 - Securities - Debt Securities by Maturity (Details) - USD ($) | Sep. 30, 2019 | Dec. 31, 2018
--- | --- | ---
Due in 2019, weighted average yield | 1.92% |
Due in 2019, amortized cost | $ 3,487,000 |
Due in 2019, fair value | $ 3,488,000 |
Due in 2020 through 2024, weighted average yield | 2.31% |
Due in 2020 through 2024, amortized cost | $ 67,321,000 |
Due in 2020 through 2024, fair value | $ 67,802,000 |
Due in 2025 through 2029, weighted average yield | 2.70% |
Due in 2025 through 2029, amortized cost | $ 113,584,000 |
Due in 2025 through 2029, fair value | $ 115,696,000 |
Due in 2030 and beyond, weighted average yield | 3.11% |
Due in 2030 and beyond, amortized cost | $ 112,686,000 |
Due in 2030 and beyond, fair value | $ 115,076,000 |
Weighted average yield | 2.78% |
Amortized cost | $ 340,141,000 | $ 347,795,000
Fair value | $ 345,533,000 | 337,366,000
Collateralized Mortgage Backed Securities [Member] |  |
No single maturity, weighted average yield | 2.87% |
No single maturity, amortized cost | $ 42,563,000 |
No single maturity, fair value | 42,971,000 |
Amortized cost | 42,563,000 | 44,263,000
Fair value | $ 42,971,000 | 43,658,000
Other Debt and Equity Securities [Member] |  |
No single maturity, weighted average yield | 4.50% |
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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