Debt Instrument, Fixed Interest Rate, Term

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- Definition

Federal Home Loan Bank, Advances, Required Collateral, Percent

+ References

No definition available.

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- Definition

Long-term Debt, Average Outstanding Amount

+ References

No definition available.

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- Definition

Long-term Debt, Maximum Amount Outstanding During Period

+ References

No definition available.

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- Definition

Private Debt Issuance Sale, Number of Institutional Investors

+ References

No definition available.

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- Definition

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

+ Details

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- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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- Definition

Discloses the single interest rate [if] applicable to the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Borrowings - Narrative (Details)				12 Months Ended
Borrowings - Narrative (Details)	Jul. 14, 2017 USD ($)	Aug. 10, 2015 USD ($)	Nov. 01, 2013 USD ($) investor	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2015 USD ($)	Sep. 15, 2012	Jul. 02, 2007 USD ($)
Debt Instrument [Line Items]
Total available remaining borrowing capacity from FHLB				$ 629,237,000
Puttable advances with the FHLB				$ 314,986,000	$ 414,377,000
Debt face amount			$ 70,000,000
Private debt issuance, number of institutional investors \| investor			4
5.00% Senior Notes Due 2028
Debt Instrument [Line Items]
Redemption price (percent)				100.00%
5% Senior Notes Due 2028 and 6.75% Subordinated Notes due 2028
Debt Instrument [Line Items]
Debt term with fixed interest rate			10 years
Putable Advances
Debt Instrument [Line Items]
Puttable advances with the FHLB				$ 45,000,000
Minimum
Debt Instrument [Line Items]
Required value of assets pledged as collateral as a percentage to outstanding advances				145.00%
Interest rate, minimum (as a percent)				0.96%
Maximum
Debt Instrument [Line Items]
Interest rate, minimum (as a percent)				5.09%
Securities Sold Under Repurchase Agreements
Debt Instrument [Line Items]
Maximum amount of outstanding agreements				$ 143,016,000	145,883,000
Total of average agreements				124,762,000	134,401,000
Debt outstanding				113,512,000
Subordinated Debentures and Term Loans
Debt Instrument [Line Items]
Debt outstanding				$ 138,463,000	$ 139,349,000
Subordinated Debenture \| 6.75% Subordinated Notes Due 2028
Debt Instrument [Line Items]
Debt face amount			$ 65,000,000
Interest rate on notes (as a percent)			6.75%
Redemption price (percent)				100.00%
Subordinated Debenture \| Three-Month LIBOR \| 6.75% Subordinated Notes Due 2028
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)				4.095%
Subordinated Debenture \| First Merchant Capital Trust II
Debt Instrument [Line Items]
Debt outstanding				$ 51,702,000
Debt face amount								$ 56,702,000
Cancellation of debt, amount		$ 5,000,000
Gain from cancellation of debt		$ 1,250,000
Interest rate on notes (as a percent)				4.35%	3.15%		6.495%
Subordinated Debenture \| First Merchant Capital Trust II \| Three-Month LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)				1.56%
Subordinated Debenture \| Ameriana Capital Trust I
Debt Instrument [Line Items]
Debt face amount						$ 10,310,000
Interest rate on notes (as a percent)				4.29%	3.09%
Basis spread on variable rate (as a percent)				1.50%
Subordinated Debenture \| Grabill Capital Trust I
Debt Instrument [Line Items]
Debt face amount	$ 10,310,000
Interest rate on notes (as a percent)				5.08%	3.96%
Basis spread on variable rate (as a percent)	2.60%
Senior Notes \| 5.00% Senior Notes Due 2028
Debt Instrument [Line Items]
Debt face amount			$ 5,000,000
Interest rate on notes (as a percent)			5.00%
Senior Notes \| Three-Month LIBOR \| 5.00% Senior Notes Due 2028
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)				2.345%