Debt Instrument, Fixed Interest Rate, Term

No definition available.

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- Definition

Debt Instrument, Repurchase Notice, Face Amount

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Long-term Debt, Average Outstanding Amount

+ References

No definition available.

+ Details

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- Definition

Long-term Debt, Maximum Amount Outstanding During Period

+ References

No definition available.

+ Details

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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.

+ References

+ Details

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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.

+ Details

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- Definition

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

+ References

+ Details

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- Definition

The average effective interest rate during the reporting period.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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- Definition

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

+ References

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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.

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- Definition

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

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- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

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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

Rate of interest applicable on advance from Federal Home Loan Bank (FHLBank).

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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No definition available.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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BORROWINGS - Narrative (Details)			9 Months Ended	12 Months Ended
BORROWINGS - Narrative (Details)	Dec. 18, 2024	Nov. 01, 2013 USD ($) investor	Sep. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Mar. 31, 2025 USD ($)	Jun. 30, 2024 USD ($)	Mar. 31, 2024 USD ($)	Dec. 18, 2019 USD ($)
Debt Instrument [Line Items]
Total available remaining borrowing capacity from FHLB				$ 733,100,000
Putable advances with the FHLB				822,554,000	$ 712,852,000
Debt face amount		$ 70,000,000
Private debt issuance, number of institutional investors \| investor		4
Senior Notes
Debt Instrument [Line Items]
Fixed interest rate term		10 years
5.00% Senior Notes Due 2028
Debt Instrument [Line Items]
Redemption price (percent)		100.00%
U.S. Bank, N.A Credit Agreement \| Line of Credit
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percent)			2.25%
Outstanding balance on the line of credit				0
Maximum borrowing capacity			$ 75,000,000
Non-refundable facility fee			0.40%
Putable Advances
Debt Instrument [Line Items]
Putable advances with the FHLB				$ 305,000,000.0
Minimum
Debt Instrument [Line Items]
Interest rate, minimum (as a percent)				1.50%
Maximum
Debt Instrument [Line Items]
Interest rate, minimum (as a percent)				4.94%
Securities Sold Under Repurchase Agreements
Debt Instrument [Line Items]
Maximum amount of outstanding agreements				$ 194,200,000	242,200,000
Total of average agreements				136,000,000.0	171,300,000
Debt outstanding				142,876,000
Subordinated Debentures and Term Loans
Debt Instrument [Line Items]
Debt outstanding				93,529,000	158,600,000
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%
Principal redemption							$ 25,000,000	$ 40,000,000
Subordinated Debenture \| Acquired Subordinated Notes
Debt Instrument [Line Items]
Debt face amount									$ 30,000,000
Interest rate on notes (as a percent)									4.75%
Debt instrument, basis spread on variable rate (as a percent)	3.11%
Subordinated Debenture \| Acquired Subordinated Notes \| Forecast
Debt Instrument [Line Items]
Notice of redemption amount						$ 30,000,000
Subordinated Debenture \| First Merchant Capital Trust II
Debt Instrument [Line Items]
Debt face amount				$ 41,700,000	$ 41,700,000
Debt instrument, basis spread on variable rate (as a percent)				26.161%	26.161%
Interest rate during the period				6.18%	7.21%
Subordinated Debenture \| Ameriana Capital Trust I
Debt Instrument [Line Items]
Debt face amount				$ 10,300,000	$ 10,300,000
Debt instrument, basis spread on variable rate (as a percent)				0.26161%	0.26161%
Interest rate during the period				6.12%	7.15%
Senior Notes
Debt Instrument [Line Items]
Debt face amount		$ 70,000,000
Private debt issuance, number of institutional investors \| investor		4
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%
Debt Instrument, Interest Rate, Effective Percentage				7.18%	7.98%
Senior Notes \| Three-Month SOFR \| 5.00% Senior Notes Due 2028
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percent)				0.26161%	0.26161%
Senior Notes \| SOFR \| 5.00% Senior Notes Due 2028
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percent)				2.345%	2.345%
Secured Debt
Debt Instrument [Line Items]
Debt outstanding				$ 7,100,000	$ 7,300,000
Interest rate on notes (as a percent)				3.41%	3.41%
Secured Debt \| Level One
Debt Instrument [Line Items]
Debt outstanding				$ 1,100,000	$ 1,200,000
Interest rate on notes (as a percent)				1.00%	1.00%