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Note 5 - Securities (Details) - Securities Held-to-maturity - USD ($) $ in Thousands | Jun. 30, 2015 | Dec. 31, 2014
--- | --- | ---
Held to Maturity: |  |
Securities held-to-maturity, amortized costs | $ 155,704 | $ 161,452
Securities held-to-maturity, gross unrealized gains | 5,488 | 7,225
Securities held-to-maturity, gross unrealized losses | 2,267 | 974
Securities held-to-maturity, fair value | 158,925 | 167,703
US Government Agencies Debt Securities [Member] |  |
Held to Maturity: |  |
Securities held-to-maturity, amortized costs | 15,914 | 18,922
Securities held-to-maturity, gross unrealized gains | 302 | 350
Securities held-to-maturity, gross unrealized losses | 428 | 245
Securities held-to-maturity, fair value | 15,788 | 19,027
US States and Political Subdivisions Debt Securities [Member] |  |
Held to Maturity: |  |
Securities held-to-maturity, amortized costs | 138,001 | 140,702
Securities held-to-maturity, gross unrealized gains | 5,133 | 6,823
Securities held-to-maturity, gross unrealized losses | 1,838 | 727
Securities held-to-maturity, fair value | 141,296 | 146,798
Collateralized Mortgage Backed Securities [Member] |  |
Held to Maturity: |  |
Securities held-to-maturity, amortized costs | 373 | 415
Securities held-to-maturity, gross unrealized gains | 47 | 51
Securities held-to-maturity, fair value | 420 | 466
Corporate Debt Securities [Member] |  |
Held to Maturity: |  |
Securities held-to-maturity, amortized costs | 1,416 | 1,413
Securities held-to-maturity, gross unrealized gains | 6 | 1
Securities held-to-maturity, gross unrealized losses | 1 | 2
Securities held-to-maturity, fair value | $ 1,421 | $ 1,412

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- Definition Amount of accumulated unrealized gain on investments in debt securities classified as held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 + Details
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- Definition Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 + Details
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