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Commitments and Contingent Liabilities - Additional Information (Detail) (USD $) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2014 complaint plaintiff | Dec. 31, 2013
Loss Contingencies [Line Items] |  |
Notional amount of financial standby letters of credit | $ 141,000 |
Notional amount of performance standby letters of credit | 400,000 |
Notional amount of commercial letters of credit | 0 |
Financial instrument of credit risk | 100,000 | 100,000
Number of new complaints | 3 |
Loss Contingency, Number of Plaintiffs | 36 |
Unused commitments and letters of credit [Member] |  |
Loss Contingencies [Line Items] |  |
Unfunded commitment liability | 2,800,000 | 3,200,000
Other Matters [Member] |  |
Loss Contingencies [Line Items] |  |
Contingency reserve | 800,000 |
Other Matters [Member] | Minimum [Member] |  |
Loss Contingencies [Line Items] |  |
Number of customers affected (in customers) | 700 |
Other Matters [Member] | Maximum [Member] |  |
Loss Contingencies [Line Items] |  |
Number of customers affected (in customers) | 900 |
Pending Litigation [Member] |  |
Loss Contingencies [Line Items] |  |
Percentage Of Interest Rate On Deposits | 3.50% |
Number of Former Plaintiffs | 34 |
Specified Average Age of Plaintiffs | 62 |
Jarrett [Member] | Pending Litigation [Member] |  |
Loss Contingencies [Line Items] |  |
Loss Contingency, Number of Plaintiffs | 8 |
Young [Member] | Pending Litigation [Member] |  |
Loss Contingencies [Line Items] |  |
Loss Contingency, Number of Plaintiffs | 12 |
Fisanik [Member] | Pending Litigation [Member] |  |
Loss Contingencies [Line Items] |  |
Loss Contingency, Number of Plaintiffs | 14 |
Ira Market Rate For Savings Account [Member] | Pending Litigation [Member] |  |
Loss Contingencies [Line Items] |  |
Percentage Of Interest Rate On Deposits | 8.00% |
Market Rate Savings Balance | $ 4,000,000 |

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- Definition Notional amount of commercial letters of credit. + References No definition available. + Details
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- Definition Notional Amount Of Financial Standby Letters Of Credit + References No definition available. + Details
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- Definition Notional amount of performance standby letters of credit. + References No definition available. + Details
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- Definition Number of new complaints + References No definition available. + Details
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- Definition Reserve for credit risk of off-balance sheet activities + References No definition available. + Details
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- Definition This item represents disclosure of all significant concentrations of credit risk or market risk arising from the subject financial instrument (as defined), whether from an individual counterparty or groups of counterparties. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.25) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 25 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 19 -Article 7 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 17 -Article 9 + Details
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