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v3.20.4

Other Borrowings - Additional Information (Detail) - USD ($) $ in Thousands |  | 1 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Nov. 01, 2017 | Apr. 30, 2020 | Mar. 31, 2020 | Feb. 29, 2020 | Dec. 31, 2020 | Dec. 31, 2019 | Aug. 31, 2014
Debt Instrument [Line Items] |  |  |  |  |  |  |
Lease liability |  |  |  |  | $ 11,813 | $ 7,406 |
Old National Bank |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Lease liability |  |  |  |  | $ 11,813 | 7,406 |
Junior Subordinated Debentures | Trust Preferred Securities |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Redemption of debentures at par |  | $ 3,100 | $ 3,100 | $ 4,100 |  |  |
Debt instrument floating rate at redemption |  | 5.62% | 4.71% | 5.36% |  |  |
Subordinated Debentures | Anchor Bank (MN) | Subordinated Fixed-To-Floating Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
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] |  |  |  |  |  |  |
Fixed rates | 5.75% |  |  |  |  |  |
LIBOR rate | 4.356% |  |  |  |  |  |
Subordinated Debt | Old National Bank |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Fixed rates |  |  |  |  | 4.57% |  |
Old National Bancorp | Senior Unsecured Notes |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Senior unsecured notes |  |  |  |  | $ 175,000 | $ 175,000 | $ 175,000
Fixed rates |  |  |  |  | 4.125% |  | 4.125%

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