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Note 6 - Investment Securities Available For Sale (Details) - Gross Unrealized Losses and Fair Value (USD $) In Thousands, unless otherwise specified | 9 Months Ended | 12 Months Ended
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Sep. 30, 2013 | Dec. 31, 2012
Note 6 - Investment Securities Available For Sale (Details) - Gross Unrealized Losses and Fair Value [Line Items] |  |
Securities in Continuous Unrealized Loss Position Less than Twelve Months Fair Value | $ 78,393 | $ 31,531
Securities in Continuous Unrealized Loss Position Less than Twelve Months Gross Unrealized Losses | (5,673) | (260)
Securities in Continuous Unrealized Loss Position Twelve Months or Greater Fair Value | 6,167 | 0
Securities in Continuous Unrealized Loss Position Twelve Months or Greater Gross Unrealized Losses | (225) | 0
Securities in Continuous Unrealized Loss Position Fair Value | 84,560 | 31,531
Securities in Continuous Unrealized Loss Position Gross Unrealized Losses | (5,898) | (260)
US Government Agencies Debt Securities [Member] |  |
Note 6 - Investment Securities Available For Sale (Details) - Gross Unrealized Losses and Fair Value [Line Items] |  |
Securities in Continuous Unrealized Loss Position Less than Twelve Months Fair Value | 17,408 | 9,938
Securities in Continuous Unrealized Loss Position Less than Twelve Months Gross Unrealized Losses | (1,368) | (91)
Securities in Continuous Unrealized Loss Position Twelve Months or Greater Fair Value | 0 | 0
Securities in Continuous Unrealized Loss Position Twelve Months or Greater Gross Unrealized Losses | 0 | 0
Securities in Continuous Unrealized Loss Position Fair Value | 17,408 | 9,938
Securities in Continuous Unrealized Loss Position Gross Unrealized Losses | (1,368) | (91)
US States and Political Subdivisions Debt Securities [Member] |  |
Note 6 - Investment Securities Available For Sale (Details) - Gross Unrealized Losses and Fair Value [Line Items] |  |
Securities in Continuous Unrealized Loss Position Less than Twelve Months Fair Value | 30,690 | 9,240
Securities in Continuous Unrealized Loss Position Less than Twelve Months Gross Unrealized Losses | (3,244) | (104)
Securities in Continuous Unrealized Loss Position Twelve Months or Greater Fair Value | 448 | 0
Securities in Continuous Unrealized Loss Position Twelve Months or Greater Gross Unrealized Losses | (40) | 0
Securities in Continuous Unrealized Loss Position Fair Value | 31,138 | 9,240
Securities in Continuous Unrealized Loss Position Gross Unrealized Losses | (3,284) | (104)
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Note 6 - Investment Securities Available For Sale (Details) - Gross Unrealized Losses and Fair Value [Line Items] |  |
Securities in Continuous Unrealized Loss Position Less than Twelve Months Fair Value | 30,295 | 12,353
Securities in Continuous Unrealized Loss Position Less than Twelve Months Gross Unrealized Losses | (1,061) | (65)
Securities in Continuous Unrealized Loss Position Twelve Months or Greater Fair Value | 5,719 | 0
Securities in Continuous Unrealized Loss Position Twelve Months or Greater Gross Unrealized Losses | (185) | 0
Securities in Continuous Unrealized Loss Position Fair Value | 36,014 | 12,353
Securities in Continuous Unrealized Loss Position Gross Unrealized Losses | $ (1,246) | $ (65)

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- Definition Amount of unrealized loss on securities classified as available-for-sale that have been in a loss position for twelve months or longer. + 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 (a)(2) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
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- Definition Amount of unrealized loss on 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 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
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