v2.4.0.8

Portfolio Loans Not Covered by Loss Share ("Non-covered") - Summary of Non-covered Loans Individually Evaluated for Impairment by Category (Details) (USD $) | 3 Months Ended | 9 Months Ended | 12 Months Ended | 9 Months Ended | 12 Months Ended | 9 Months Ended | 12 Months Ended | 9 Months Ended | 12 Months Ended | 9 Months Ended | 12 Months Ended | 9 Months Ended | 12 Months Ended | 9 Months Ended | 12 Months Ended |  |
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Sep. 30, 2013 loan | Sep. 30, 2013 loan | Sep. 30, 2013 Non-Covered Loans | Dec. 31, 2012 Non-Covered Loans | Sep. 30, 2013 Non-Covered Loans Commercial & Industrial | Dec. 31, 2012 Non-Covered Loans Commercial & Industrial | Sep. 30, 2013 Non-Covered Loans Commercial Real Estate Owner Occupied | Dec. 31, 2012 Non-Covered Loans Commercial Real Estate Owner Occupied | Sep. 30, 2013 Non-Covered Loans Commercial Real Estate Investor Owned | Dec. 31, 2012 Non-Covered Loans Commercial Real Estate Investor Owned | Sep. 30, 2013 Non-Covered Loans Construction and Land Development | Dec. 31, 2012 Non-Covered Loans Construction and Land Development | Sep. 30, 2013 Non-Covered Loans Residential Real Estate | Dec. 31, 2012 Non-Covered Loans Residential Real Estate | Sep. 30, 2013 Non-Covered Loans Consumer & Other | Dec. 31, 2012 Non-Covered Loans Consumer & Other | Sep. 30, 2013 Unadvanced Commitment on Impaired Loan | Dec. 31, 2012 Unadvanced Commitment on Impaired Loan
Financing Receivable, Impaired [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unpaid Contractual Principal Balance |  |  | $ 26,399,000 | $ 45,218,000 | $ 6,333,000 | $ 9,005,000 | $ 191,000 | $ 6,726,000 | $ 11,969,000 | $ 19,864,000 | $ 7,206,000 | $ 6,491,000 | $ 700,000 | $ 3,132,000 | $ 0 | $ 0 |  |
Recorded Investment With No Allowance |  |  | 11,334,000 | 5,645,000 | 1,441,000 | 96,000 | 195,000 | 2,178,000 | 4,960,000 | 185,000 | 4,278,000 | 1,560,000 | 460,000 | 1,626,000 | 0 | 0 |  |
Recorded Investment With Allowance |  |  | 13,416,000 | 33,082,000 | 4,642,000 | 8,838,000 | 0 | 3,594,000 | 6,158,000 | 16,577,000 | 2,389,000 | 3,135,000 | 227,000 | 938,000 | 0 | 0 |  |
Total Recorded Investment |  |  | 24,750,000 | 38,727,000 | 6,083,000 | 8,934,000 | 195,000 | 5,772,000 | 11,118,000 | 16,762,000 | 6,667,000 | 4,695,000 | 687,000 | 2,564,000 | 0 | 0 |  |
Related Allowance |  |  | 4,306,000 | 8,176,000 | 2,610,000 | 3,446,000 | 0 | 339,000 | 973,000 | 3,400,000 | 712,000 | 732,000 | 11,000 | 259,000 | 0 | 0 |  |
Average Recorded Investment |  |  | 29,632,000 | 39,491,000 | 7,379,000 | 6,379,000 | 2,381,000 | 7,985,000 | 12,346,000 | 10,500,000 | 5,165,000 | 10,259,000 | 2,361,000 | 4,368,000 | 0 | 0 |  |
Table Text Block Supplement [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of loans over 90 days past due and still accruing | 0 | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest lost on impaired loans | 410,000 | 1,453,643 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Impaired Financing Receivable, Interest Income, Cash Basis Method | 4,000 | 28,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Impaired Financing Receivable, Interest Income, Accrual Method | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loans and Leases Receivable, Impaired Loans, Commitment to Lend |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,724,000 | 775,000
Estimated losses attributable to unadvanced commitments on impaired loans |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 241,000 | $ 124,000

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