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Loans and Allowance for Loan Losses - Recorded Principal Balance of Nonaccrual Loans (Detail) (USD $) | Sep. 30, 2013 | Dec. 31, 2012
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Financing Receivable Recorded Investment Nonaccrual Loans [Line Items] |  |
Total nonaccrual loans | $ 10,526,000 | $ 18,970,000
Commercial and Industrial [Member] |  |
Financing Receivable Recorded Investment Nonaccrual Loans [Line Items] |  |
Total nonaccrual loans | 1,581,000 | 1,677,000
Commercial Vacant Land, Land Development, and Residential Construction [Member] |  |
Financing Receivable Recorded Investment Nonaccrual Loans [Line Items] |  |
Total nonaccrual loans | 922,000 | 2,194,000
Commercial Real Estate - Owner Occupied [Member] |  |
Financing Receivable Recorded Investment Nonaccrual Loans [Line Items] |  |
Total nonaccrual loans | 570,000 | 2,087,000
Commercial Real Estate - Non-Owner Occupied [Member] |  |
Financing Receivable Recorded Investment Nonaccrual Loans [Line Items] |  |
Total nonaccrual loans | 4,642,000 | 9,010,000
Commercial Real Estate - Multi-Family and Residential Rental [Member] |  |
Financing Receivable Recorded Investment Nonaccrual Loans [Line Items] |  |
Total nonaccrual loans | 764,000 | 2,021,000
Commercial Loans [Member] |  |
Financing Receivable Recorded Investment Nonaccrual Loans [Line Items] |  |
Total nonaccrual loans | 8,479,000 | 16,989,000
Retail Home Equity and Other [Member] |  |
Financing Receivable Recorded Investment Nonaccrual Loans [Line Items] |  |
Total nonaccrual loans | 805,000 | 889,000
Retail 1-4 Family Mortgages [Member] |  |
Financing Receivable Recorded Investment Nonaccrual Loans [Line Items] |  |
Total nonaccrual loans | 1,242,000 | 1,092,000
Retail Loans [Member] |  |
Financing Receivable Recorded Investment Nonaccrual Loans [Line Items] |  |
Total nonaccrual loans | $ 2,047,000 | $ 1,981,000

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- Details
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- Definition Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5111-111524 + Details
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