ALLOWANCE FOR CREDIT LOSSES - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans transferred to held for sale	$ 352,744	$ 0
Rocky Mountain Bank
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing receivable, excluding accrued interest, transfer out, expense reversal		$ 2,000
Loans transferred to held for sale	$ 352,700

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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Amount, excluding accrued interest, of reversal of credit loss expense on financing receivable transferred out of held-for-investment into held-for-sale classification. Excludes net investment in lease.

+ References

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Value of loans and leases held in the entity's portfolio transferred to loans and leases held-for-sale in noncash transactions.

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