FAIR VALUE MEASUREMENTS - Schedule of Estimated Non-recurring Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Financial Assets
Trading securities	$ 6,400	$ 6,700
Equity securities	12,868	12,856
Securities available for sale, at fair value	1,340,331	1,423,200
Securities held to maturity	487,960	507,464
Carrying Amount
Financial Assets
Cash and cash equivalents	640,600	685,355
Trading securities	6,405	6,708
Equity securities	12,868	12,856
Securities available for sale, at fair value	1,340,331	1,423,200
Securities held to maturity	563,765	583,453
Federal Home Loan Bank stock	34,714	7,219
Net loans	8,782,183	8,239,039
Loans held for sale	8,708	4,311
Accrued interest receivable	50,580	46,868
Derivative assets	52,736	54,241
Financial Liabilities
Total deposits	10,068,407	10,327,269
Short-term debt	470,000	0
Long-term Federal Home Loan Bank advances and other	204,345	4,445
Subordinated borrowings	121,238	121,064
Accrued interest payable	7,096	1,610
Derivative liabilities	94,656	97,030
Fair Value
Financial Assets
Cash and cash equivalents	640,600	685,355
Trading securities	6,405	6,708
Equity securities	12,868	12,856
Securities available for sale, at fair value	1,340,331	1,423,200
Securities held to maturity	487,960	507,464
Net loans	8,727,074	8,194,110
Loans held for sale	8,708	4,311
Accrued interest receivable	50,580	46,868
Derivative assets	52,736	54,241
Financial Liabilities
Total deposits	10,035,236	10,283,543
Short-term debt	469,935	0
Long-term Federal Home Loan Bank advances and other	196,824	2,782
Subordinated borrowings	100,739	110,853
Accrued interest payable	7,096	1,610
Derivative liabilities	94,656	97,030
Level 1
Financial Assets
Cash and cash equivalents	640,600	685,355
Trading securities	0	0
Equity securities	12,868	12,856
Securities available for sale, at fair value	7,981	11,973
Securities held to maturity	0	0
Net loans	0	0
Loans held for sale	0	0
Accrued interest receivable	0	0
Derivative assets	0	0
Financial Liabilities
Total deposits	0	0
Short-term debt	0	0
Long-term Federal Home Loan Bank advances and other	0	0
Subordinated borrowings	0	0
Accrued interest payable	0	0
Derivative liabilities	0	0
Level 2
Financial Assets
Cash and cash equivalents	0	0
Trading securities	0	0
Equity securities	0	0
Securities available for sale, at fair value	1,328,420	1,407,227
Securities held to maturity	486,313	505,508
Net loans	0	0
Loans held for sale	8,708	942
Accrued interest receivable	50,580	46,868
Derivative assets	52,636	54,216
Financial Liabilities
Total deposits	10,035,236	10,283,543
Short-term debt	469,935	0
Long-term Federal Home Loan Bank advances and other	196,824	2,782
Subordinated borrowings	100,739	110,853
Accrued interest payable	7,096	1,610
Derivative liabilities	94,656	97,030
Level 3
Financial Assets
Cash and cash equivalents	0	0
Trading securities	6,405	6,708
Equity securities	0	0
Securities available for sale, at fair value	3,930	4,000
Securities held to maturity	1,647	1,956
Net loans	8,727,074	8,194,110
Loans held for sale	0	3,369
Accrued interest receivable	0	0
Derivative assets	100	25
Financial Liabilities
Total deposits	0	0
Short-term debt	0	0
Long-term Federal Home Loan Bank advances and other	0	0
Subordinated borrowings	0	0
Accrued interest payable	0	0
Derivative liabilities	$ 0	$ 0

Accrued Interest Payable, Fair Value Disclosure

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This element represent as Federal Home Loan Bank Stock And Other Restricted Securities, Excluding Accrued Interest

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount excluding accrued interest, 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 portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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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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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount of short-term debt existing as of the balance sheet date.

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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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