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Note 8 - Fair Value Measurements (Details) - Level 3 Fair Value Measurements | 6 Months Ended | 12 Months Ended
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Jun. 30, 2013 | Dec. 31, 2012
Discounted Appraised Value [Member] | Impaired loans [Member] |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |
Fair value, valuation technique | Discounted appraised value |  | Discounted appraised value |
Fair value, unobservable input |  | [1] |  |
Fair value, valuation technique | Discounted appraised value |  | Discounted appraised value |
Fair value, valuation technique | Discounted appraised value |  | Discounted appraised value |
Discounted Appraised Value [Member] | Other Real Estate Owned [Member] |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |
Fair value, valuation technique | Discounted appraised value |  | Discounted appraised value |
Fair value, valuation technique | Discounted appraised value |  | Discounted appraised value |
Fair value, valuation technique | Discounted appraised value |  | Discounted appraised value |
Discounted Appraised Value [Member] | Minimum [Member] | Impaired loans [Member] |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |
Fair value, unobservable input |  |  | 0.00% |
Fair value, unobservable input |  |  | 0.00% |
Discounted Appraised Value [Member] | Minimum [Member] | Other Real Estate Owned [Member] |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |
Fair value, unobservable input |  | [2] |  | [2]
Fair value, unobservable input | 0.00% |  | 0.00% |
Discounted Appraised Value [Member] | Maximum [Member] | Impaired loans [Member] |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |
Fair value, unobservable input |  |  | 10.00% |
Fair value, unobservable input |  |  | 60.00% |
Discounted Appraised Value [Member] | Maximum [Member] | Other Real Estate Owned [Member] |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |
Fair value, unobservable input | 9.95% |  | 6.00% |
Fair value, unobservable input | 3.65% |  | 30.90% |
Discounted Appraised Value [Member] | Weighted Average [Member] | Impaired loans [Member] |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |
Fair value, unobservable input |  |  | (2.00%) |
Fair value, unobservable input |  |  | (52.00%) |
Discounted Appraised Value [Member] | Weighted Average [Member] | Other Real Estate Owned [Member] |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |
Fair value, unobservable input | (2.66%) |  | (4.30%) |
Fair value, unobservable input | (0.61%) |  | (4.68%) |
Present Value of Cash Flows [Member] | Impaired loans [Member] |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |
Fair value, valuation technique | Present value of cash flows |  | Present value of cash flows |
Fair value, valuation technique | Present value of cash flows |  | Present value of cash flows |
Fair value, valuation technique | Present value of cash flows |  | Present value of cash flows |
Present Value of Cash Flows [Member] | Minimum [Member] | Impaired loans [Member] |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |
Fair value, unobservable input | 6.25% |  | 6.00% |
Present Value of Cash Flows [Member] | Maximum [Member] | Impaired loans [Member] |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |
Fair value, unobservable input | 7.75% |  | 7.50% |
Present Value of Cash Flows [Member] | Weighted Average [Member] | Impaired loans [Member] |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |
Fair value, unobservable input | (6.63%) |  | (6.28%) |
[1] | Of the Company's impaired loans with specific allocations based on Level 3 inputs, only one loan was valued using fair value of collateral.
[2] | The Company markets other real estate owned both independently and with local realtors. Properties marketed by realtors are discounted by selling costs. Properties that the Company markets independently are not discounted by selling costs.

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- Definition Refers to the rate of selling cost. + References No definition available. + Details
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- Definition Adjustment to the discount rate used to measure fair value for lack of ability to convert business interests into cash quickly. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 + Details
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- Definition Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 + Details
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- Definition Description of the inputs and valuation technique(s) used to measure fair value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 + Details
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