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Loans and Allowance for Loan Losses (Details 4) (USD $) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2012 | Sep. 30, 2011 | Sep. 30, 2012 | Sep. 30, 2011 | Dec. 31, 2011
Impaired loans |  |  |  |  |
Impaired loans, Related Allowance | $ 15,802,000 |  | $ 15,802,000 |  | $ 18,996,000
Impaired loans, Unpaid Contractual Principal Balance | 78,570,000 |  | 78,570,000 |  | 97,771,000
Impaired loans, Recorded Principal Balance | 63,214,000 |  | 63,214,000 |  | 70,978,000
Impaired loans, Year-To-Date Average Recorded Principal Balance |  |  | 62,328,000 | 58,180,000 |
Impaired Loans, Third Quarter Average Recorded Principal Balance | 57,418,000 | 46,191,000 |  |  |
Total commercial [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Impaired loans, Related Allowance | 15,497,000 |  | 15,497,000 |  | 18,645,000
Impaired loans, Unpaid Contractual Principal Balance | 75,831,000 |  | 75,831,000 |  | 94,668,000
Impaired loans, Recorded Principal Balance | 61,378,000 |  | 61,378,000 |  | 68,893,000
Impaired loans, Year-To-Date Average Recorded Principal Balance |  |  | 60,267,000 | 55,203,000 |
Impaired Loans, Third Quarter Average Recorded Principal Balance | 55,427,000 | 43,441,000 |  |  |
Total retail [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Impaired loans, Related Allowance | 305,000 |  | 305,000 |  | 351,000
Impaired loans, Unpaid Contractual Principal Balance | 2,739,000 |  | 2,739,000 |  | 3,103,000
Impaired loans, Recorded Principal Balance | 1,836,000 |  | 1,836,000 |  | 2,085,000
Impaired loans, Year-To-Date Average Recorded Principal Balance |  |  | 2,061,000 | 2,977,000 |
Impaired Loans, Third Quarter Average Recorded Principal Balance | 1,991,000 | 2,750,000 |  |  |
Impaired loans with no related allowance [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with no related allowance | 22,752,000 |  | 22,752,000 |  | 33,129,000
Recorded Principal Balance, with no related allowance | 14,931,000 |  | 14,931,000 |  | 20,839,000
Average Recorded Principal Balance, with no related allowance | 16,027,000 | 19,786,000 | 18,024,000 | 26,340,000 |
Impaired loans with no related allowance [Member] | Commercial and industrial [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with no related allowance | 4,210,000 |  | 4,210,000 |  | 4,670,000
Recorded Principal Balance, with no related allowance | 3,289,000 |  | 3,289,000 |  | 4,254,000
Average Recorded Principal Balance, with no related allowance | 3,209,000 | 1,353,000 | 3,521,000 | 1,704,000 |
Impaired loans with no related allowance [Member] | Vacant land, land development, and residential construction [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with no related allowance | 2,279,000 |  | 2,279,000 |  | 5,308,000
Recorded Principal Balance, with no related allowance | 1,166,000 |  | 1,166,000 |  | 2,755,000
Average Recorded Principal Balance, with no related allowance | 1,480,000 | 2,278,000 | 1,959,000 | 6,387,000 |
Impaired loans with no related allowance [Member] | Real estate - owner occupied [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with no related allowance | 4,578,000 |  | 4,578,000 |  | 5,525,000
Recorded Principal Balance, with no related allowance | 3,246,000 |  | 3,246,000 |  | 3,572,000
Average Recorded Principal Balance, with no related allowance | 3,391,000 | 4,071,000 | 3,535,000 | 4,233,000 |
Impaired loans with no related allowance [Member] | Real estate - non-owner occupied [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with no related allowance | 7,493,000 |  | 7,493,000 |  | 14,017,000
Recorded Principal Balance, with no related allowance | 4,979,000 |  | 4,979,000 |  | 8,131,000
Average Recorded Principal Balance, with no related allowance | 5,832,000 | 9,286,000 | 6,850,000 | 12,306,000 |
Impaired loans with no related allowance [Member] | Real estate - multi-family and residential rental [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with no related allowance | 2,172,000 |  | 2,172,000 |  | 1,309,000
Recorded Principal Balance, with no related allowance | 985,000 |  | 985,000 |  | 671,000
Average Recorded Principal Balance, with no related allowance | 918,000 | 1,579,000 | 841,000 | 979,000 |
Impaired loans with no related allowance [Member] | Total commercial [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with no related allowance | 20,732,000 |  | 20,732,000 |  | 30,829,000
Recorded Principal Balance, with no related allowance | 13,665,000 |  | 13,665,000 |  | 19,383,000
Average Recorded Principal Balance, with no related allowance | 14,830,000 | 18,567,000 | 16,706,000 | 25,609,000 |
Impaired loans with no related allowance [Member] | Retail home equity and other [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with no related allowance | 580,000 |  | 580,000 |  | 1,000,000
Recorded Principal Balance, with no related allowance | 487,000 |  | 487,000 |  | 727,000
Average Recorded Principal Balance, with no related allowance | 482,000 | 856,000 | 603,000 | 503,000 |
Impaired loans with no related allowance [Member] | Retail 1-4 family mortgages [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with no related allowance | 1,440,000 |  | 1,440,000 |  | 1,300,000
Recorded Principal Balance, with no related allowance | 779,000 |  | 779,000 |  | 729,000
Average Recorded Principal Balance, with no related allowance | 715,000 | 363,000 | 715,000 | 228,000 |
Impaired loans with no related allowance [Member] | Total retail [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with no related allowance | 2,020,000 |  | 2,020,000 |  | 2,300,000
Recorded Principal Balance, with no related allowance | 1,266,000 |  | 1,266,000 |  | 1,456,000
Average Recorded Principal Balance, with no related allowance | 1,197,000 | 1,219,000 | 1,318,000 | 731,000 |
Impaired loans with an allowance [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with related allowance | 55,818,000 |  | 55,818,000 |  | 64,642,000
Recorded Principal Balance, with related allowance | 48,283,000 |  | 48,283,000 |  | 50,139,000
Impaired loans, Related Allowance | 15,802,000 |  | 15,802,000 |  | 18,996,000
Impaired Loans, Average Recorded Principal Balance | 41,391,000 | 26,405,000 | 44,304,000 | 31,840,000 |
Impaired loans with an allowance [Member] | Commercial and industrial [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with related allowance | 3,278,000 |  | 3,278,000 |  | 3,500,000
Recorded Principal Balance, with related allowance | 2,785,000 |  | 2,785,000 |  | 3,023,000
Impaired loans, Related Allowance | 1,358,000 |  | 1,358,000 |  | 1,172,000
Impaired Loans, Average Recorded Principal Balance | 3,528,000 | 4,886,000 | 3,406,000 | 6,422,000 |
Impaired loans with an allowance [Member] | Vacant land, land development, and residential construction [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with related allowance | 3,305,000 |  | 3,305,000 |  | 5,551,000
Recorded Principal Balance, with related allowance | 3,117,000 |  | 3,117,000 |  | 4,267,000
Impaired loans, Related Allowance | 1,465,000 |  | 1,465,000 |  | 1,799,000
Impaired Loans, Average Recorded Principal Balance | 2,981,000 | 2,064,000 | 3,529,000 | 3,814,000 |
Impaired loans with an allowance [Member] | Real estate - owner occupied [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with related allowance | 3,233,000 |  | 3,233,000 |  | 8,544,000
Recorded Principal Balance, with related allowance | 2,813,000 |  | 2,813,000 |  | 7,039,000
Impaired loans, Related Allowance | 1,326,000 |  | 1,326,000 |  | 2,180,000
Impaired Loans, Average Recorded Principal Balance | 4,120,000 | 4,205,000 | 5,235,000 | 5,821,000 |
Impaired loans with an allowance [Member] | Real estate - non-owner occupied [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with related allowance | 40,590,000 |  | 40,590,000 |  | 32,331,000
Recorded Principal Balance, with related allowance | 34,521,000 |  | 34,521,000 |  | 22,009,000
Impaired loans, Related Allowance | 10,061,000 |  | 10,061,000 |  | 7,319,000
Impaired Loans, Average Recorded Principal Balance | 25,220,000 | 11,291,000 | 23,085,000 | 10,650,000 |
Impaired loans with an allowance [Member] | Real estate - multi-family and residential rental [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with related allowance | 4,693,000 |  | 4,693,000 |  | 13,913,000
Recorded Principal Balance, with related allowance | 4,477,000 |  | 4,477,000 |  | 13,172,000
Impaired loans, Related Allowance | 1,287,000 |  | 1,287,000 |  | 6,175,000
Impaired Loans, Average Recorded Principal Balance | 4,748,000 | 2,428,000 | 8,306,000 | 2,887,000 |
Impaired loans with an allowance [Member] | Total commercial [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with related allowance | 55,099,000 |  | 55,099,000 |  | 63,839,000
Recorded Principal Balance, with related allowance | 47,713,000 |  | 47,713,000 |  | 49,510,000
Impaired loans, Related Allowance | 15,497,000 |  | 15,497,000 |  | 18,645,000
Impaired Loans, Average Recorded Principal Balance | 40,597,000 | 24,874,000 | 43,561,000 | 29,594,000 |
Impaired loans with an allowance [Member] | Retail home equity and other [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with related allowance | 235,000 |  | 235,000 |  | 286,000
Recorded Principal Balance, with related allowance | 206,000 |  | 206,000 |  | 229,000
Impaired loans, Related Allowance | 206,000 |  | 206,000 |  | 215,000
Impaired Loans, Average Recorded Principal Balance | 291,000 | 753,000 | 259,000 | 1,314,000 |
Impaired loans with an allowance [Member] | Retail 1-4 family mortgages [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with related allowance | 484,000 |  | 484,000 |  | 517,000
Recorded Principal Balance, with related allowance | 364,000 |  | 364,000 |  | 400,000
Impaired loans, Related Allowance | 99,000 |  | 99,000 |  | 136,000
Impaired Loans, Average Recorded Principal Balance | 503,000 | 778,000 | 484,000 | 932,000 |
Impaired loans with an allowance [Member] | Total retail [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with related allowance | 719,000 |  | 719,000 |  | 803,000
Recorded Principal Balance, with related allowance | 570,000 |  | 570,000 |  | 629,000
Impaired loans, Related Allowance | 305,000 |  | 305,000 |  | 351,000
Impaired Loans, Average Recorded Principal Balance | $ 794,000 | $ 1,531,000 | $ 743,000 | $ 2,246,000 |

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