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Other Borrowings - Additional Information (Details) - USD ($) $ in Thousands	Jan. 29, 2026	Dec. 31, 2025	Dec. 31, 2024
Debt Instrument [Line Items]
Other borrowings		$ 25,798	$ 24,822
Subordinated Note Maturing January 2026 | Subordinated Debt | Subsequent Event
Debt Instrument [Line Items]
Issuance Amount	$ 450,000
Interest rate	5.768%
LIBOR rate	2.20%
Old National Bank
Debt Instrument [Line Items]
Other borrowings		$ 25,798	$ 24,822

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