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

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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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

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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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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Latest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

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Earliest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

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- Definition

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

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Including the current and noncurrent portions, carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Junior Subordinated Notes, which have a lower priority than senior instruments.

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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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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 (Detail) - USD ($) $ in Thousands		3 Months Ended
	Nov. 01, 2017	Mar. 31, 2019	Dec. 31, 2018	Aug. 31, 2014
Debt Instrument [Line Items]
Finance Leases, Lease liability		$ 7,432
Old National Bank [Member]
Debt Instrument [Line Items]
Finance Leases, Lease liability		7,432	$ 5,262
Anchor Bank Mn \| Trust Preferred Securities [Member]
Debt Instrument [Line Items]
Junior subordinated debentures (variable rates of 3.93% to 6.39%) maturing April 2032 to June 2037	$ 15,000,000
Subordinated Debentures [Member] \| Anchor Bank Mn \| Subordinated Fixed-To-Floating Notes [Member]
Debt Instrument [Line Items]
Fixed rates	5.75%
Maturity Date	Oct. 30, 2025
Value of subordinated fixed-to-floating notes assumed	$ 12,000
Subordinated debentures, maturity date	Oct. 29, 2020
Description of LIBOR Rate	three-month LIBOR rate plus 4.356%
LIBOR rate	4.356%
Debt instrument start date	Oct. 30, 2020
Old National Bancorp [Member] \| Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Senior unsecured notes		$ 175,000	$ 175,000	$ 175,000
Fixed rates		4.125%		4.125%
Maturity Date		Aug. 15, 2024