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Loans and Allowance for Loan Losses - Loans Modified as Troubled Debt Restructurings (Detail) (USD $) | 12 Months Ended
--- | ---
Dec. 31, 2013 Contract | Dec. 31, 2012 Contract
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modification, Number of Contracts | 10 | 29
Financing Receivable Modification, Pre-Modification Recorded Principal Balance | $ 7,231,000 | $ 32,089,000
Financing Receivable Modification, Post-Modification Recorded Principal Balance | 7,231,000 | 32,084,000
Commercial and industrial [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modification, Number of Contracts | 3 | 8
Financing Receivable Modification, Pre-Modification Recorded Principal Balance | 741,000 | 1,357,000
Financing Receivable Modification, Post-Modification Recorded Principal Balance | 741,000 | 1,353,000
Vacant land, land development and residential construction [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modification, Number of Contracts | 2 | 0
Financing Receivable Modification, Pre-Modification Recorded Principal Balance | 3,610,000 | 0
Financing Receivable Modification, Post-Modification Recorded Principal Balance | 3,610,000 | 0
Real estate - owner occupied [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modification, Number of Contracts | 2 | 6
Financing Receivable Modification, Pre-Modification Recorded Principal Balance | 715,000 | 1,745,000
Financing Receivable Modification, Post-Modification Recorded Principal Balance | 715,000 | 1,744,000
Real estate - non-owner occupied [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modification, Number of Contracts | 1 | 15
Financing Receivable Modification, Pre-Modification Recorded Principal Balance | 45,000 | 28,987,000
Financing Receivable Modification, Post-Modification Recorded Principal Balance | 45,000 | 28,987,000
Real estate - multi-family and residential rental [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modification, Number of Contracts | 1 | 0
Financing Receivable Modification, Pre-Modification Recorded Principal Balance | 241,000 | 0
Financing Receivable Modification, Post-Modification Recorded Principal Balance | 241,000 | 0
Commercial Loans [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modification, Number of Contracts | 9 | 29
Financing Receivable Modification, Pre-Modification Recorded Principal Balance | 5,352,000 | 32,089,000
Financing Receivable Modification, Post-Modification Recorded Principal Balance | 5,352,000 | 32,084,000
Home equity and other [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modification, Number of Contracts | 0 | 0
Financing Receivable Modification, Pre-Modification Recorded Principal Balance | 0 | 0
Financing Receivable Modification, Post-Modification Recorded Principal Balance | 0 | 0
1 - 4 family mortgages [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modification, Number of Contracts | 1 | 0
Financing Receivable Modification, Pre-Modification Recorded Principal Balance | 1,879,000 | 0
Financing Receivable Modification, Post-Modification Recorded Principal Balance | 1,879,000 | 0
Retail Loans [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modification, Number of Contracts | 1 | 0
Financing Receivable Modification, Pre-Modification Recorded Principal Balance | 1,879,000 | 0
Financing Receivable Modification, Post-Modification Recorded Principal Balance | $ 1,879,000 | $ 0

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