NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING AND REPORTING POLICIES - Additional Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Cash paid for:
Interest	$ 184,394	$ 188,644	$ 144,868
U.S. federal income taxes, net of refunds received	18,500	27,400	13,491
State income/franchise taxes, net of refunds received	217	359	207
Operating lease liabilities	4,222	4,625	4,586
Significant non-cash transactions
Loans transferred to other real estate	15,647	5,991	0
Bank-financed sales of other real estate	4,360	0	0
Lease right-of-use assets obtained in exchange for lessee operating lease liabilities	1,477	353	1,406
Branch assets transferred to assets held for sale	$ 0	$ 0	$ 3,819

Branch Assets Transferred To Held For Sale

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Loans transferred to other real estate.

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Other real estate transferred to loans.

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Amount, after income tax refund received, of cash paid to federal (national) tax jurisdiction for tax on income.

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Amount, after income tax refund received, of cash paid to state and local tax jurisdictions for tax on income.

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Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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