LOAN SERVICING ACTIVITIES - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
LOAN SERVICING ACTIVITIES
Bank held borrowers' escrow balances	$ 1,300	$ 1,300
Fair value of SRAs	$ 3,400	$ 3,500
Weighted average default rate	0.67	0.67
Total loans, net of fair value hedge basis point adjustments	$ 10,773,428	$ 10,566,831
Real estate and C&I loans
LOAN SERVICING ACTIVITIES
Total loans, net of fair value hedge basis point adjustments	$ 346,100	$ 347,900
Minimum
LOAN SERVICING ACTIVITIES
Discount rates	10.00%	9.50%
Prepayment speeds	6.50%	6.70%
Maximum
LOAN SERVICING ACTIVITIES
Discount rates	14.50%	12.00%
Prepayment speeds	12.20%	16.00%

Estimated weighted average default rate on financial assets regardless of when the transfer occurred.

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- Definition

Discount rate which is used to value residual cash flows generated by financial assets of a securitization, asset-backed financing arrangement, or similar transfer regardless of when the transfer occurred.

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Estimated rate of prepayment of principal on financial assets regardless of when the transfer occurred.

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- Definition

Carrying amount as of the balance sheet date of cash collateral held for borrowed securities, for which the cash is restricted as to withdrawal or usage.

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- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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- Definition

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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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