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Note 6 - Investment Securities Available For Sale (Details) (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) [Line Items] |  |
Available-for-sale Securities Pledged as Collateral | $ 73,800,000 | $ 62,500,000
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 103 |
Percentage of Portfolio | 97.00% |
Available-for-sale Securities, Current | 180,771,000 | 194,473,000
Available-for-sale Securities, Gross Unrealized Gain | 3,334,000 | 8,427,000
Private Label Collateralized Mortgage Obligations [Member] |  |
Note 6 - Investment Securities Available For Sale (Details) [Line Items] |  |
Available-for-sale Securities, Current | 3,600,000 |
Mortgage-backed Securities, Issued by Private Enterprises [Member] |  |
Note 6 - Investment Securities Available For Sale (Details) [Line Items] |  |
Available-for-sale Securities, Current | 3,974,000 | 5,064,000
Available-for-sale Securities, Gross Unrealized Gain | $ 377,000 | $ 511,000

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- Definition Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer. + 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 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26626-111562 + 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 Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
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- Definition The fair value of available-for-sale securities that serve as collateral for borrowings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5086-111524 + Details
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