| **Goodwill**                       | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
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| **Goodwill Disclosure [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| Goodwill                           | GOODWILLOn November 12, 2013, the Corporation acquired 100 percent of CFS in an all stock transaction, as discussed in NOTE 3. BUSINESS COMBINATIONS, in the Notes to Consolidated Financial Statements included as Item 8 of this Annual Report on Form 10-K.  This purchase resulted in goodwill of $47,573,000.In July 2012, FMIG acquired a book of business that resulted in goodwill acquired of $18,000.  This transaction was deemed to be an immaterial transaction.No impairment loss was recorded in 2013 or 2012.  The Corporation tested goodwill for impairment during 2012 and 2013.  In both valuations, the fair value exceeded the Corporation’s carrying value; therefore, it was concluded goodwill is not impaired. For additional details related to impairment testing, see the “GOODWILL” section of Management’s Discussion and Analysis of Financial Condition and Results of Operations included as Item 7 of this Annual Report on Form 10-K. 2013 2012Balance, January 1$141,375 $141,357Goodwill acquired47,573 18Balance, December 31$188,948 $141,375 |

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| - Definition
The entire disclosure for goodwill.
+ References
No definition available.
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