| **Income Tax (Details) (USD $)In Thousands, unless otherwise specified**                                                  | 3 Months Ended | 12 Months Ended |
|---------------------------------------------------------------------------------------------------------------------------|----------------|-----------------|
||
| **Currently Payable:**                                                                                                    |           |            |   |   |   |   |   |   |   |   |   |
| Federal                                                                                                                   |           |            |   |   |   |   |   |   | $ 738 | $ (23) | $ 399 |
| **Deferred:**                                                                                                             |           |            |   |   |   |   |   |   |   |   |   |
| Federal                                                                                                                   |           |            |   |   |   |   |   |   | 13,939 | 15,890 | 8,256 |
| Total Income Tax Expense                                                                                                  | 3,187          | 2,667           | 4,155 | 4,668 | 3,153 | 3,926 | 3,288 | 5,500 | 14,677 | 15,867 | 8,655 |
| **Reconciliation of Federal Statutory to Actual Tax Expense:**                                                            |           |            |   |   |   |   |   |   |   |   |   |
| Federal Statutory Income Tax at 35%                                                                                       |           |            |   |   |   |   |   |   | 20,722 | 21,347 | 11,867 |
| Tax-exempt Interest Income                                                                                                |           |            |   |   |   |   |   |   | (3,923) | (3,716) | (3,714) |
| Non-deductible Interest Expense                                                                                           |           |            |   |   |   |   |   |   |    |    | 649 |
| Stock Compensation                                                                                                        |           |            |   |   |   |   |   |   | 50 | 76 | 69 |
| Earnings on Life Insurance                                                                                                |           |            |   |   |   |   |   |   | (905) | (1,187) | (899) |
| Tax Credits                                                                                                               |           |            |   |   |   |   |   |   | (857) | (73) | (99) |
| Other                                                                                                                     |           |            |   |   |   |   |   |   | (410) | (580) | 782 |
| Total Income Tax Expense                                                                                                  | 3,187          | 2,667           | 4,155 | 4,668 | 3,153 | 3,926 | 3,288 | 5,500 | 14,677 | 15,867 | 8,655 |
| Tax expense applicable to security gains and losses, including unrealized losses relating to other-than-temporary charges |           |            |   |   |   |   |   |   | $ 157 | $ 759 | $ 714 |

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Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.
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Amount of deferred federal income tax expense (benefit) pertaining to income (loss) from continuing operations.
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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.
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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other deductions.
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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.
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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income (loss) exempt from income taxes.
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