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Loans and Allowance for Loan Losses (Details 2) (USD $) | Sep. 30, 2012 | Dec. 31, 2011
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Recorded principal balance of nonaccrual loans, including troubled debt restructurings |  |
Nonaccrual loans | $ 24,782,000 | $ 45,074,000
Commercial and industrial [Member] |  |
Recorded principal balance of nonaccrual loans, including troubled debt restructurings |  |
Nonaccrual loans | 3,870,000 | 5,916,000
Vacant land, land development, and residential construction [Member] |  |
Recorded principal balance of nonaccrual loans, including troubled debt restructurings |  |
Nonaccrual loans | 2,850,000 | 3,448,000
Real estate - owner occupied [Member] |  |
Recorded principal balance of nonaccrual loans, including troubled debt restructurings |  |
Nonaccrual loans | 3,074,000 | 6,635,000
Real estate - non-owner occupied [Member] |  |
Recorded principal balance of nonaccrual loans, including troubled debt restructurings |  |
Nonaccrual loans | 11,157,000 | 24,169,000
Real estate - multi-family and residential rental [Member] |  |
Recorded principal balance of nonaccrual loans, including troubled debt restructurings |  |
Nonaccrual loans | 1,754,000 | 2,532,000
Total commercial [Member] |  |
Recorded principal balance of nonaccrual loans, including troubled debt restructurings |  |
Nonaccrual loans | 22,705,000 | 42,700,000
Retail home equity and other [Member] |  |
Recorded principal balance of nonaccrual loans, including troubled debt restructurings |  |
Nonaccrual loans | 733,000 | 1,013,000
Retail 1-4 family mortgages [Member] |  |
Recorded principal balance of nonaccrual loans, including troubled debt restructurings |  |
Nonaccrual loans | 1,344,000 | 1,361,000
Total retail [Member] |  |
Recorded principal balance of nonaccrual loans, including troubled debt restructurings |  |
Nonaccrual loans | $ 2,077,000 | $ 2,374,000

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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=7512638&loc=d3e5111-111524 + Details
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