| **Purchase and Assumption (SCB Bank)** | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                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| SCB Bank                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               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| **Business Acquisition [Line Items]**  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               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| Purchase and Assumption                | PURCHASE AND ASSUMPTION Effective February 10, 2012, First Merchants Bank, National Association (the “Bank”) assumed substantially all of the deposits and certain other liabilities and acquired certain assets of SCB Bank, a federal savings bank headquartered in Shelbyville, Indiana, from the Federal Deposit Insurance Corporation (“FDIC”), as receiver for SCB Bank (the “Acquisition”), pursuant to the terms of the Purchase and Assumption Agreement – Modified Whole Bank; All Deposits (the “Agreement”), entered into by the Bank, the FDIC as receiver of SCB Bank and the FDIC.Under the terms of the Agreement, the Bank acquired $147.7 million in assets, including approximately $11.9 million of cash and cash equivalents, $18.9 million of marketable securities, $1.8 million in Federal Home Loan Bank stock, $113.0 million in loans and $2.1 million of premises and other assets.  The Bank assumed approximately $135.7 million of liabilities, including approximately $125.9 million in customer deposits, $9.6 million of other borrowed money and $402,000 in other liabilities.  These balances are book balances and do not reflect the fair value adjustments which are shown on the following table.  The acquisition did not include any loss sharing agreement with the FDIC.The bid accepted by the FDIC included no deposit premium.  The assets were acquired at a discount of $29.0 million from book value.  The FDIC made a payment of $17.2 million to the Bank upon the final closing date balance sheet for SCB Bank that reflected the difference between the purchase price of the assets acquired and the value of the liabilities assumed.The Bank engaged in this transaction with the expectation that it would be immediately accretive and add a new market area with a demographic profile consistent with many of the current Indiana markets served by the Bank.The transaction was accounted for under the acquisition method of accounting in accordance with the Business Combination topic of the FASB Accounting Standards Codification (“ASC 310-20 and 310-30”).  The statement of net assets and liabilities acquired as of February 10, 2012, are presented below.  The assets and liabilities of SCB were recorded at the respective acquisition date provisional fair values, and identifiable intangible assets were recorded at provisional fair value. Assets  Liabilities Cash and due from banks (1)$29,113 Deposits: Investment securities, available for sale18,896 Non-interest bearing$13,715Federal Home Loan Bank stock1,761 NOW accounts14,746Loans:  Savings and money market25,843Commercial51,042 Certificate of deposit71,605Residential mortgage11,181 Total Deposits125,909Installment31,570   Total Loans93,793 Federal Home Loan Bank advances10,286   Other liabilities804Premises1,516 Total Liabilities Assumed$136,999Core deposit intangible484   Other assets560 Net Gain on Acquisition$9,124Total Assets Purchased$146,123     (1)Includes $17,200,000 cash received from the FDIC.In many cases, the fair values of assets acquired and liabilities assumed were determined by estimating cash flows expected to result from those assets and liabilities and discounting them at appropriate market rates.  The most significant category of assets for which this procedure was used was acquired loans.  The Bank acquired the $113.0 million loan portfolio at a fair value discount of $19.2 million.  The performing portion of the portfolio, $86.3 million, had an estimated fair value of $76.5 million.  The excess of expected cash flows above the fair value of the performing portion of loans will be accreted to interest income over the remaining lives of the loans in accordance with ASC 310-20.  Discounts or premiums on term loans are accounted for under an effective yield method.  Prepayments on term loans are accounted for in the effective yield calculation.  Discounts or premiums on lines of credit are treated in a straight line method over the term of the lines of credit.Certain loans for which specific credit-related deterioration has occurred since origination are recorded at fair value which is derived from calculating the present value of the amounts expected to be collected.  Income recognition on these loans is based on reasonable expectation about the timing and amount of cash flows to be collected.  Some of the acquired loans deemed impaired and considered collateral dependent, with the timing of a sale of loan collateral indeterminate, remain on non-accrual status and have little to no accretable yield.In accordance with ASC 310-30 (formerly Statement of Position (“SOP”) 03-3 as of February 10, 2012, loans acquired during 2012 for which it was probable at acquisition that all contractually required payments would not be collected are as follows: Preliminary estimate of contractually required principal and interest at acquisition$31,143Preliminary estimate of contractual cash flows not expected to be collected (nonaccretable differences)9,688Preliminary estimate of expected cash flows at acquisition21,455Preliminary estimate of interest component of expected cash flows (accretable discount)4,152Preliminary estimate of fair value of acquired loans accounted for under ASC 310-30$17,303  Pro-forma statements were determined to be impracticable due to the nature of the transaction as certain assets were not purchased. |

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| - Definition
The entire disclosure for a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. The disclosure may include leverage buyout transactions (as applicable).
+ References
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