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Loans and Allowance for Loan Losses (Details Textual) (USD $) | 12 Months Ended
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Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
Loans and Allowance for Loan Losses (Textual) [Abstract] |  |  |
Accrued troubled debt restructurings included in nonperforming loans | $ 0 | $ 0 |
Adoption of troubled debt restructuring guidance |  | 26,200,000 |
Related Allowance |  | 5,700,000 |
Interest income recognized on impaired loans | 2,000,000 | 200,000 | 200,000
Lost interest income on nonaccrual loans | $ 800,000 | $ 1,400,000 | $ 2,100,000
Number of past due days for loans modified as TDR | 30 days | 30 days |

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- Definition Increase in related allowance for impaired loans resulting from adoption of troubled debt restructuring guidance. + References No definition available. + Details
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- Definition Increase in unpaid contractual principal balance and recorded principal balance resulting from adoption of troubled debt restructuring guidance. + References No definition available. + Details
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- Details
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- Definition Number of past due days for loans modified as TDR. + References No definition available. + Details
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- Definition The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6951948&loc=d3e18845-111554 + Details
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- Definition Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5212-111524 + Details
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- Definition Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 114 -Paragraph 20 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Section 563c.102 -Paragraph 8 -Subparagraph j(ii) -Chapter V -Subsection I -LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. It will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 15 -Paragraph 40 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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