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Commitments and Off-Balance Sheet Risk (Details Textual) (USD $) |  |  |  | 6 Months Ended
--- | --- | --- | --- | ---
Jun. 30, 2013 | Dec. 31, 2012 | Jun. 30, 2013 Interest rate swap agreement [Member] | Jun. 30, 2013 Maximum [Member] | Jun. 30, 2013 Minimum [Member]
Commitments and Off-Balance Sheet Risk (Textual) [Abstract] |  |  |  |  |
Fees accreted into income during interest rate swap agreements years |  |  |  | 15 years | 4 years
Notional amount of the underlying interest rate swap agreements entered into by commercial loan customers with correspondent banks |  |  | $ 18,500,000 |  |
Commitments and Off-Balance Sheet Risk (Additional Textual) [Abstract] |  |  |  |  |
Reserve or liability balance for financial instruments with off-balance sheet risk | 0 | 0 |  |  |
Net fair value of interest rate swaps entered into by commercial loan customers with correspondent banks | $ (2,800,000) |  |  |  |

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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Definition Fees accreted into income during interest rate swap agreements years. + References No definition available. + Details
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- Definition Fair value of the assets less the liabilities of a derivative or group of derivatives. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13433-108611 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13495-108611 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958 + Details
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