FAIR VALUE OF FINANCIAL INSTRUMENTS (Assets and Liabilities on Recurring and Non-Recurring Basis) (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities	$ 14	$ 13
Money market investments	4,674	4,623	$ 3,172
Servicing assets	49,553	49,520	49,345	$ 50,921
Foreclosed real estate	10,850	10,780	$ 9,250	$ 11,214
Other repossessed assets	6,844	4,032
Recurring fair value measurements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	1,897,707	2,099,264
Trading securities	14	13
Money market investments	4,674	4,623
Servicing assets	49,553	49,520
Total	1,951,948	2,153,420
Recurring fair value measurements \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	150,915	296,799
Trading securities	0	0
Money market investments	4,674	4,623
Servicing assets	0	0
Total	155,589	301,422
Recurring fair value measurements \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	1,746,792	1,802,465
Trading securities	14	13
Money market investments	0	0
Servicing assets	0	0
Total	1,746,806	1,802,478
Recurring fair value measurements \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	0	0
Trading securities	0	0
Money market investments	0	0
Servicing assets	49,553	49,520
Total	49,553	49,520
Non-recurring fair value measurements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent loans	7,862	8,027
Foreclosed real estate	10,850	10,780
Other repossessed assets	6,844	4,032
Mortgage loans held for sale	9,370
Other loans held for sale	18,904	28,345
Total	53,830	51,184
Non-recurring fair value measurements \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent loans	0	0
Foreclosed real estate	0	0
Other repossessed assets	0	0
Mortgage loans held for sale	0
Other loans held for sale	0	0
Total	0	0
Non-recurring fair value measurements \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent loans	0	0
Foreclosed real estate	0	0
Other repossessed assets	0	0
Mortgage loans held for sale	0
Other loans held for sale	0	0
Total	0	0
Non-recurring fair value measurements \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent loans	7,862	8,027
Foreclosed real estate	10,850	10,780
Other repossessed assets	6,844	4,032
Mortgage loans held for sale	9,370
Other loans held for sale	18,904	28,345
Total	$ 53,830	$ 51,184

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value of asset after deduction of liability.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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Fair value portion of mortgage loans held-for-sale.

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Carrying amount as of the balance sheet date of assets other than real property that were received in full or partial satisfaction of a debt arrangement through foreclosure proceedings or defeasance.

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Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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