| **Contingent Liabilities**                              | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
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| **Commitments and Contingencies Disclosure [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| Contingent Liabilities                                  | CONTINGENT LIABILITIESOn April 16, 2013, First Merchants was named in a class action lawsuit in Delaware County Circuit Court challenging First Merchant's checking account practices associated with the assessment of overdraft fees.  The plaintiff sought damages and other relief, including restitution and injunctive relief.  First Merchants removed the case from state court to federal district court.  First Merchants then filed a motion to stay the federal action pending arbitration.  The motion was granted by the court and the action was stayed.  To the extent the plaintiff desires to further pursue the matter, the plaintiff must do so through a separate arbitration proceeding.  To date, there has been no effort by the plaintiff to initiate arbitration proceedings and no further activity in the court proceedings.  If arbitration is pursued, First Merchants believes it has meritorious defenses to the claims brought by the plaintiff. |

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| - Definition
The entire disclosure for legal proceedings, legal contingencies, litigation, regulatory and environmental matters and other contingencies.
+ References
No definition available.
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