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Loans and Allowance for Loan Losses (Details 4) (USD $) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012 | Dec. 31, 2012
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with no related allowance | $ 17,634,000 |  | $ 17,634,000 |  | $ 20,038,000
Recorded Principal Balance, with no related allowance | 10,522,000 |  | 10,522,000 |  | 11,752,000
Average Recorded Principal Balance, with no related allowance | 10,726,000 | 18,164,000 |  |  |
Year-To-Date Average Recorded Principal Balance, with no related allowance |  |  | 11,068,000 | 19,055,000 |
Impaired loans, Unpaid Contractual Principal Balance | 61,634,000 |  | 61,634,000 |  | 69,166,000
Impaired loans, Recorded Principal Balance | 53,677,000 |  | 53,677,000 |  | 57,279,000
Impaired Loans, Second Quarter Average Recorded Principal Balance | 52,689,000 | 57,561,000 |  |  |
Impaired loans, Year-To-Date Average Recorded Principal Balance |  |  | 54,219,000 | 62,033,000 |
Unpaid Contractual Principal Balance, with related allowance | 44,000,000 |  | 44,000,000 |  | 49,128,000
Recorded Principal Balance, with related allowance | 43,155,000 |  | 43,155,000 |  | 45,527,000
Impaired loans, Related Allowance | 14,836,000 |  | 14,836,000 |  | 17,189,000
Impaired Loans, Average Recorded Principal Balance | 41,963,000 | 39,397,000 |  |  |
Year-To-Date Average Recorded Principal Balance, with related allowance |  |  | 43,151,000 | 42,978,000 |
Commercial and industrial [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with no related allowance | 2,793,000 |  | 2,793,000 |  | 1,926,000
Recorded Principal Balance, with no related allowance | 1,277,000 |  | 1,277,000 |  | 1,617,000
Average Recorded Principal Balance, with no related allowance | 1,416,000 | 3,270,000 |  |  |
Year-To-Date Average Recorded Principal Balance, with no related allowance |  |  | 1,483,000 | 3,598,000 |
Unpaid Contractual Principal Balance, with related allowance | 1,708,000 |  | 1,708,000 |  | 3,221,000
Recorded Principal Balance, with related allowance | 1,587,000 |  | 1,587,000 |  | 1,926,000
Impaired loans, Related Allowance | 1,154,000 |  | 1,154,000 |  | 924,000
Impaired Loans, Average Recorded Principal Balance | 2,046,000 | 3,909,000 |  |  |
Year-To-Date Average Recorded Principal Balance, with related allowance |  |  | 2,006,000 | 3,613,000 |
Vacant land, land development, and residential construction [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with no related allowance | 1,543,000 |  | 1,543,000 |  | 2,356,000
Recorded Principal Balance, with no related allowance | 1,010,000 |  | 1,010,000 |  | 1,401,000
Average Recorded Principal Balance, with no related allowance | 1,194,000 | 1,958,000 |  |  |
Year-To-Date Average Recorded Principal Balance, with no related allowance |  |  | 1,263,000 | 2,224,000 |
Unpaid Contractual Principal Balance, with related allowance | 5,058,000 |  | 5,058,000 |  | 2,333,000
Recorded Principal Balance, with related allowance | 4,515,000 |  | 4,515,000 |  | 2,219,000
Impaired loans, Related Allowance | 1,223,000 |  | 1,223,000 |  | 1,367,000
Impaired Loans, Average Recorded Principal Balance | 2,998,000 | 3,366,000 |  |  |
Year-To-Date Average Recorded Principal Balance, with related allowance |  |  | 2,738,000 | 3,667,000 |
Real estate - owner occupied [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with no related allowance | 2,020,000 |  | 2,020,000 |  | 2,368,000
Recorded Principal Balance, with no related allowance | 1,383,000 |  | 1,383,000 |  | 1,557,000
Average Recorded Principal Balance, with no related allowance | 1,366,000 | 3,661,000 |  |  |
Year-To-Date Average Recorded Principal Balance, with no related allowance |  |  | 1,430,000 | 3,631,000 |
Unpaid Contractual Principal Balance, with related allowance | 2,402,000 |  | 2,402,000 |  | 4,307,000
Recorded Principal Balance, with related allowance | 2,350,000 |  | 2,350,000 |  | 3,626,000
Impaired loans, Related Allowance | 922,000 |  | 922,000 |  | 1,388,000
Impaired Loans, Average Recorded Principal Balance | 2,652,000 | 5,545,000 |  |  |
Year-To-Date Average Recorded Principal Balance, with related allowance |  |  | 2,976,000 | 6,043,000 |
Real estate - non-owner occupied [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with no related allowance | 8,067,000 |  | 8,067,000 |  | 9,984,000
Recorded Principal Balance, with no related allowance | 5,194,000 |  | 5,194,000 |  | 5,492,000
Average Recorded Principal Balance, with no related allowance | 4,956,000 | 7,145,000 |  |  |
Year-To-Date Average Recorded Principal Balance, with no related allowance |  |  | 5,134,000 | 7,473,000 |
Unpaid Contractual Principal Balance, with related allowance | 29,249,000 |  | 29,249,000 |  | 33,818,000
Recorded Principal Balance, with related allowance | 29,233,000 |  | 29,233,000 |  | 32,964,000
Impaired loans, Related Allowance | 9,672,000 |  | 9,672,000 |  | 11,773,000
Impaired Loans, Average Recorded Principal Balance | 29,778,000 | 17,904,000 |  |  |
Year-To-Date Average Recorded Principal Balance, with related allowance |  |  | 30,840,000 | 19,272,000 |
Real estate - multi-family and residential rental [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with no related allowance | 1,468,000 |  | 1,468,000 |  | 1,188,000
Recorded Principal Balance, with no related allowance | 514,000 |  | 514,000 |  | 413,000
Average Recorded Principal Balance, with no related allowance | 599,000 | 855,000 |  |  |
Year-To-Date Average Recorded Principal Balance, with no related allowance |  |  | 537,000 | 794,000 |
Unpaid Contractual Principal Balance, with related allowance | 2,589,000 |  | 2,589,000 |  | 4,471,000
Recorded Principal Balance, with related allowance | 2,527,000 |  | 2,527,000 |  | 3,923,000
Impaired loans, Related Allowance | 835,000 |  | 835,000 |  | 1,408,000
Impaired Loans, Average Recorded Principal Balance | 2,609,000 | 7,787,000 |  |  |
Year-To-Date Average Recorded Principal Balance, with related allowance |  |  | 3,047,000 | 9,582,000 |
Total commercial [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with no related allowance | 15,891,000 |  | 15,891,000 |  | 17,822,000
Recorded Principal Balance, with no related allowance | 9,378,000 |  | 9,378,000 |  | 10,480,000
Average Recorded Principal Balance, with no related allowance | 9,531,000 | 16,889,000 |  |  |
Year-To-Date Average Recorded Principal Balance, with no related allowance |  |  | 9,847,000 | 17,720,000 |
Impaired loans, Unpaid Contractual Principal Balance | 56,897,000 |  | 56,897,000 |  | 65,972,000
Impaired loans, Recorded Principal Balance | 49,590,000 |  | 49,590,000 |  | 55,138,000
Impaired Loans, Second Quarter Average Recorded Principal Balance | 49,614,000 | 55,400,000 |  |  |
Impaired loans, Year-To-Date Average Recorded Principal Balance |  |  | 51,454,000 | 59,897,000 |
Unpaid Contractual Principal Balance, with related allowance | 41,006,000 |  | 41,006,000 |  | 48,150,000
Recorded Principal Balance, with related allowance | 40,212,000 |  | 40,212,000 |  | 44,658,000
Impaired loans, Related Allowance | 13,806,000 |  | 13,806,000 |  | 16,860,000
Impaired Loans, Average Recorded Principal Balance | 40,083,000 | 38,511,000 |  |  |
Year-To-Date Average Recorded Principal Balance, with related allowance |  |  | 41,607,000 | 42,177,000 |
Retail Home equity and other [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with no related allowance | 508,000 |  | 508,000 |  | 580,000
Recorded Principal Balance, with no related allowance | 468,000 |  | 468,000 |  | 483,000
Average Recorded Principal Balance, with no related allowance | 474,000 | 600,000 |  |  |
Year-To-Date Average Recorded Principal Balance, with no related allowance |  |  | 477,000 | 642,000 |
Unpaid Contractual Principal Balance, with related allowance | 350,000 |  | 350,000 |  | 423,000
Recorded Principal Balance, with related allowance | 324,000 |  | 324,000 |  | 394,000
Impaired loans, Related Allowance | 134,000 |  | 134,000 |  | 204,000
Impaired Loans, Average Recorded Principal Balance | 335,000 | 300,000 |  |  |
Year-To-Date Average Recorded Principal Balance, with related allowance |  |  | 355,000 | 277,000 |
Retail 1-4 family mortgages [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with no related allowance | 1,235,000 |  | 1,235,000 |  | 1,636,000
Recorded Principal Balance, with no related allowance | 676,000 |  | 676,000 |  | 789,000
Average Recorded Principal Balance, with no related allowance | 721,000 | 675,000 |  |  |
Year-To-Date Average Recorded Principal Balance, with no related allowance |  |  | 744,000 | 693,000 |
Unpaid Contractual Principal Balance, with related allowance | 2,644,000 |  | 2,644,000 |  | 555,000
Recorded Principal Balance, with related allowance | 2,619,000 |  | 2,619,000 |  | 475,000
Impaired loans, Related Allowance | 896,000 |  | 896,000 |  | 125,000
Impaired Loans, Average Recorded Principal Balance | 1,545,000 | 586,000 |  |  |
Year-To-Date Average Recorded Principal Balance, with related allowance |  |  | 1,189,000 | 524,000 |
Total retail [Member] |  |  |  |  |
Impaired loans |  |  |  |  |
Unpaid Contractual Principal Balance, with no related allowance | 1,743,000 |  | 1,743,000 |  | 2,216,000
Recorded Principal Balance, with no related allowance | 1,144,000 |  | 1,144,000 |  | 1,272,000
Average Recorded Principal Balance, with no related allowance | 1,195,000 | 1,275,000 |  |  |
Year-To-Date Average Recorded Principal Balance, with no related allowance |  |  | 1,221,000 | 1,335,000 |
Impaired loans, Unpaid Contractual Principal Balance | 4,737,000 |  | 4,737,000 |  | 3,194,000
Impaired loans, Recorded Principal Balance | 4,087,000 |  | 4,087,000 |  | 2,141,000
Impaired Loans, Second Quarter Average Recorded Principal Balance | 3,075,000 | 2,161,000 |  |  |
Impaired loans, Year-To-Date Average Recorded Principal Balance |  |  | 2,765,000 | 2,136,000 |
Unpaid Contractual Principal Balance, with related allowance | 2,994,000 |  | 2,994,000 |  | 978,000
Recorded Principal Balance, with related allowance | 2,943,000 |  | 2,943,000 |  | 869,000
Impaired loans, Related Allowance | 1,030,000 |  | 1,030,000 |  | 329,000
Impaired Loans, Average Recorded Principal Balance | 1,880,000 | 886,000 |  |  |
Year-To-Date Average Recorded Principal Balance, with related allowance |  |  | $ 1,544,000 | $ 801,000 |

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