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Loans and Allowance for Loan Losses - Loans, Modified As Troubled Debt Restructurings within the Previous Twelve Months, That Became Over 30 Days Past Due (Detail) (USD $) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2013 Contract | Sep. 30, 2012 Contract | Sep. 30, 2013 Contract | Sep. 30, 2012 Contract
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Contracts | 0 | 0 | 0 | 0
Recorded Principal Balance | $ 0 | $ 0 | $ 0 | $ 0
Commercial Loans [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Contracts | 0 | 0 | 0 | 0
Recorded Principal Balance | 0 | 0 | 0 | 0
Commercial Loans [Member] | Commercial and industrial [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Contracts | 0 | 0 | 0 | 0
Recorded Principal Balance | 0 | 0 | 0 | 0
Commercial Loans [Member] | Vacant land, land development and residential construction [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Contracts | 0 | 0 | 0 | 0
Recorded Principal Balance | 0 | 0 | 0 | 0
Commercial Loans [Member] | Real estate - owner occupied [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Contracts | 0 | 0 | 0 | 0
Recorded Principal Balance | 0 | 0 | 0 | 0
Commercial Loans [Member] | Real estate - non-owner occupied [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Contracts | 0 | 0 | 0 | 0
Recorded Principal Balance | 0 | 0 | 0 | 0
Commercial Loans [Member] | Real estate - multi-family and residential rental [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Contracts | 0 | 0 | 0 | 0
Recorded Principal Balance | 0 | 0 | 0 | 0
Retail Loans [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Contracts | 0 | 0 | 0 | 0
Recorded Principal Balance | 0 | 0 | 0 | 0
Retail Loans [Member] | Home equity and other [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Contracts | 0 | 0 | 0 | 0
Recorded Principal Balance | 0 | 0 | 0 | 0
Retail Loans [Member] | 1 - 4 family mortgages [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Contracts | 0 | 0 | 0 | 0
Recorded Principal Balance | $ 0 | $ 0 | $ 0 | $ 0

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- Definition Financing receivables modifications subsequent default recorded investment. + References No definition available. + Details
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- Details
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