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Note 3 - Securities - Available-for-sale Securities (Details) - USD ($) | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Amortized cost | $ 329,979,000 | $ 347,795,000
Securities available for sale, gross unrealized gains | 5,930,000 | 928,000
Securities available for sale, gross unrealized losses | (1,254,000) | (11,357,000)
Fair value | 334,655,000 | 337,366,000
US Government Agencies Debt Securities [Member] |  |
Amortized cost | 185,103,000 | 196,109,000
Securities available for sale, gross unrealized gains | 2,449,000 | 310,000
Securities available for sale, gross unrealized losses | (1,142,000) | (9,342,000)
Fair value | 186,410,000 | 187,077,000
Collateralized Mortgage Backed Securities [Member] |  |
Amortized cost | 41,998,000 | 44,263,000
Securities available for sale, gross unrealized gains | 554,000 | 187,000
Securities available for sale, gross unrealized losses | (82,000) | (792,000)
Fair value | 42,470,000 | 43,658,000
Municipal General Obligation Bonds [Member] |  |
Amortized cost | 98,245,000 | 103,235,000
Securities available for sale, gross unrealized gains | 2,864,000 | 427,000
Securities available for sale, gross unrealized losses | (30,000) | (1,165,000)
Fair value | 101,079,000 | 102,497,000
Municipal Revenue Bonds [Member] |  |
Amortized cost | 4,133,000 | 3,688,000
Securities available for sale, gross unrealized gains | 63,000 | 4,000
Securities available for sale, gross unrealized losses | 0 | (58,000)
Fair value | 4,196,000 | 3,634,000
Other Debt and Equity Securities [Member] |  |
Amortized cost | 500,000 | 500,000
Securities available for sale, gross unrealized gains | 0 | 0
Securities available for sale, gross unrealized losses | 0 | 0
Fair value | $ 500,000 | $ 500,000

X
- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563 + Details
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- Definition Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563 + Details
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