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Note 2 - Securities (Details) - Available-for-sale Securities - USD ($) | Sep. 30, 2015 | Dec. 31, 2014
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Schedule of Available-for-sale Securities [Line Items] |  |  |
Securities available for sale, amortized cost |  | $ 365,456,000 | $ 432,591,000
Securities available for sale, gross unrealized gains |  | 4,060,000 | 3,897,000
Securities available for sale, gross unrealized losses |  | (2,343,000) | (3,576,000)
Securities available for sale | [1] | 367,173,000 | 432,912,000
US Government Agencies Debt Securities [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Securities available for sale, amortized cost |  | 159,411,000 | 194,894,000
Securities available for sale, gross unrealized gains |  | 1,939,000 | 1,612,000
Securities available for sale, gross unrealized losses |  | (1,957,000) | (3,038,000)
Securities available for sale |  | 159,393,000 | 193,468,000
Collateralized Mortgage Backed Securities [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Securities available for sale, amortized cost |  | 72,211,000 | 92,656,000
Securities available for sale, gross unrealized gains |  | 904,000 | 1,123,000
Securities available for sale, gross unrealized losses |  | (151,000) | (218,000)
Securities available for sale |  | 72,964,000 | 93,561,000
Municipal General Obligation Bonds [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Securities available for sale, amortized cost |  | 122,724,000 | 132,347,000
Securities available for sale, gross unrealized gains |  | 1,118,000 | 1,042,000
Securities available for sale, gross unrealized losses |  | (234,000) | (307,000)
Securities available for sale |  | 123,608,000 | 133,082,000
Municipal Revenue Bonds [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Securities available for sale, amortized cost |  | 9,163,000 | 10,769,000
Securities available for sale, gross unrealized gains |  | 88,000 | 117,000
Securities available for sale, gross unrealized losses |  | (1,000) | (13,000)
Securities available for sale |  | 9,250,000 | 10,873,000
Other Debt Obligations [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Securities available for sale, amortized cost |  | 1,947,000 | 1,925,000
Securities available for sale, gross unrealized gains |  | 11,000 | 3,000
Securities available for sale, gross unrealized losses |  | 0 | 0
Securities available for sale |  | $ 1,958,000 | $ 1,928,000
[1] | See Note 11 for a description of the fair value hierarchy as well as a disclosure of levels for classes of financial assets and liabilities.

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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49167202&loc=d3e26610-111562 + Details
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- Definition Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 + Details
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