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Note 6 - Investment Securities Available For Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale (USD $) | 9 Months Ended | 12 Months Ended
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Sep. 30, 2013 | Dec. 31, 2012
Note 6 - Investment Securities Available For Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Available for Sale Securities Amortized Cost | $ 183,335,000 | $ 186,305,000
Available for Sale Securities Gross Unrealized Gains | 3,334,000 | 8,427,000
Available for Sale Securities Gross Unrealized Losses | (5,898,000) | (260,000)
Available for Sale Securities Fair Value | 180,771,000 | 194,472,000
Taxable [Member] | US States and Political Subdivisions Debt Securities [Member] |  |
Note 6 - Investment Securities Available For Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Available for Sale Securities Amortized Cost | 5,364,000 | 6,888,000
Available for Sale Securities Gross Unrealized Gains | 215,000 | 738,000
Available for Sale Securities Gross Unrealized Losses | (21,000) | 0
Available for Sale Securities Fair Value | 5,558,000 | 7,626,000
Tax-exempt [Member] | US States and Political Subdivisions Debt Securities [Member] |  |
Note 6 - Investment Securities Available For Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Available for Sale Securities Amortized Cost | 90,441,000 | 80,391,000
Available for Sale Securities Gross Unrealized Gains | 1,885,000 | 4,684,000
Available for Sale Securities Gross Unrealized Losses | (3,263,000) | (104,000)
Available for Sale Securities Fair Value | 89,063,000 | 84,971,000
US Government Agencies Debt Securities [Member] |  |
Note 6 - Investment Securities Available For Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Available for Sale Securities Amortized Cost | 27,550,000 | 24,485,000
Available for Sale Securities Gross Unrealized Gains | 161,000 | 566,000
Available for Sale Securities Gross Unrealized Losses | (1,368,000) | (91,000)
Available for Sale Securities Fair Value | 26,343,000 | 24,960,000
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Note 6 - Investment Securities Available For Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Available for Sale Securities Amortized Cost | 55,633,000 | 69,238,000
Available for Sale Securities Gross Unrealized Gains | 696,000 | 1,929,000
Available for Sale Securities Gross Unrealized Losses | (1,246,000) | (65,000)
Available for Sale Securities Fair Value | 55,083,000 | 71,102,000
Mortgage-backed Securities, Issued by Private Enterprises [Member] |  |
Note 6 - Investment Securities Available For Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Available for Sale Securities Amortized Cost | 3,597,000 | 4,553,000
Available for Sale Securities Gross Unrealized Gains | 377,000 | 511,000
Available for Sale Securities Gross Unrealized Losses | 0 | 0
Available for Sale Securities Fair Value | 3,974,000 | 5,064,000
Debt Securities [Member] |  |
Note 6 - Investment Securities Available For Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Available for Sale Securities Amortized Cost | 182,585,000 | 185,555,000
Available for Sale Securities Gross Unrealized Gains | 3,334,000 | 8,427,000
Available for Sale Securities Gross Unrealized Losses | (5,898,000) | (260,000)
Available for Sale Securities Fair Value | 180,021,000 | 193,723,000
Equity Securities in Financial Institutions [Member] |  |
Note 6 - Investment Securities Available For Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Available for Sale Securities Amortized Cost | 750,000 | 750,000
Available for Sale Securities Gross Unrealized Gains | 0 | 0
Available for Sale Securities Gross Unrealized Losses | 0 | 0
Available for Sale Securities Fair Value | $ 750,000 | $ 750,000

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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=28360136&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=6871852&loc=d3e26610-111562 + Details
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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities. + 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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- Definition Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities. + 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 (c) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 + Details
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