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Fair Value Measurements (Details 3) (USD $) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2013 | Dec. 31, 2012
Assets: |  |
Impaired Loans | $ 70,267,000 | $ 73,646,000
Assumptions used in discounted cash flow model to determine fair value of investments classified within level 3 |  |
Charges to allowance for probable loan losses in connection with other real estate owned | 61,000 | 10,450,000
Adjustment to fair value in connection with other real estate owned | (70,000) | 0
Impaired commercial collateral dependent loans | 70,267,000 | 73,646,000
Impaired commerical collateral dependent receivables appraisals to determine fair value within last twelve months | 50,579,000 | 48,856,000
Significant Unobservable Inputs (Level 3) | Bond meeting the original contract terms |  |
Assumptions used in discounted cash flow model to determine fair value of investments classified within level 3 |  |
Estimated future principal prepayment rate assumption, low end of range (as a percent) | 7.00% |
Estimated future principal prepayment rate assumption, discount rate (as a percent) | 13.00% |
Default rate assumptions (as a percent) | 1.00% |
Loss severity rate assumptions, first year (as a percent) | 25.00% |
Significant Unobservable Inputs (Level 3) | Bond not meeting the original contract terms |  |
Assumptions used in discounted cash flow model to determine fair value of investments classified within level 3 |  |
Estimated future principal prepayment rate assumption, low end of range (as a percent) | 2.00% |
Estimated future principal prepayment rate assumption, discount rate (as a percent) | 13.00% |
Default rate assumptions (as a percent) | 4.50% |
Loss severity rate assumptions, first year (as a percent) | 60.00% |
Decrease in loss severity rates, following five years (as a percent) | 5.00% |
Loss severity rate, thereafter (as a percent) | 25.00% |
Measured on a non-recurring basis: |  |
Assumptions used in discounted cash flow model to determine fair value of investments classified within level 3 |  |
Change in net provision (Credit), impaired loans | 10,332,000 | 295,000
Change in net provision (Credit), other real estate owned | (70,000) |
Measured on a non-recurring basis: | Assets/Liabilities Measured at Fair Value |  |
Assets: |  |
Impaired Loans | 27,330,000 | 11,981,000
Non-financial assets: |  |
Other real estate owned | 2,752,000 | 18,749,000
Assumptions used in discounted cash flow model to determine fair value of investments classified within level 3 |  |
Impaired commercial collateral dependent loans | 27,330,000 | 11,981,000
Measured on a non-recurring basis: | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Impaired Loans | 27,330,000 | 11,981,000
Non-financial assets: |  |
Other real estate owned | 2,752,000 | 18,749,000
Assumptions used in discounted cash flow model to determine fair value of investments classified within level 3 |  |
Impaired commercial collateral dependent loans | $ 27,330,000 | $ 11,981,000

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