FAIR VALUE MEASUREMENTS - Measured on Non-recurring Basis (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Assets
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Noninterest Income	Noninterest Income
Non-recurring \| Level 3
Assets
Individually evaluated loans	$ 3,500	$ 16,477
Capitalized servicing rights	6,764	6,845
Premises held for sale	1,154	252
Total	11,418	$ 23,574
Total Gains (Losses)	(12,156)
Non-recurring \| Level 3 \| Impaired loans
Assets
Total Gains (Losses)	(12,977)
Non-recurring \| Level 3 \| Capitalized servicing rights
Assets
Total Gains (Losses)	(81)
Non-recurring \| Level 3 \| Assets held for sale
Assets
Total Gains (Losses)	$ 902

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Fair value portion of assets classified as held for sale.

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Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

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Indicates line item in statement in which net income is reported that includes gain (loss) from liability measured at fair value using unobservable input (level 3).

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The balance of financing receivables that were individually evaluated for impairment.

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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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