The amount of financial liabilities assumed (as defined) which have been recognized as of the acquisition date.

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

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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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Present value of lessee's discounted obligation for lease payments from finance lease.

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

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Carrying value as of the balance sheet date of uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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Other Borrowings - Additional Information (Details) - USD ($) $ in Thousands	Nov. 01, 2017	Mar. 31, 2022	Feb. 15, 2022	Dec. 31, 2021	Aug. 31, 2014
Debt Instrument [Line Items]
Lease liability		$ 16,621		$ 17,233
Old National Bank
Debt Instrument [Line Items]
Lease liability		16,621		17,233
First Midwest
Debt Instrument [Line Items]
Subordinated debentures			$ 150,000
Subordinated Debentures \| Anchor Bank (MN) \| Subordinated Fixed-to-Floating Notes
Debt Instrument [Line Items]
Fixed rate	5.75%
Value of subordinated fixed-to-floating notes assumed	$ 12,000
Subordinated Debentures \| Anchor Bank (MN) \| Subordinated Fixed-to-Floating Notes \| LIBOR
Debt Instrument [Line Items]
Variable rate	4.356%
Old National Bancorp \| Senior Unsecured Notes
Debt Instrument [Line Items]
Senior unsecured notes		$ 175,000		$ 175,000	$ 175,000
Fixed rate		4.125%			4.125%