INVESTMENTS - Narrative (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Fair Value, Separate Account Investment [Line Items]
Accrued interest receivable	$ 45,162	$ 46,583
Book value of debt securities pledged as collateral	1,460,058	1,456,984
Asset pledged as collateral \| Deposits
Fair Value, Separate Account Investment [Line Items]
Book value of debt securities pledged as collateral	435,800	729,000
Collateralized mortgage obligations
Fair Value, Separate Account Investment [Line Items]
Mortgage-backed securities	470,500
Collateralized mortgage backed securities
Fair Value, Separate Account Investment [Line Items]
Mortgage-backed securities	556,000
SBA asset backed securities
Fair Value, Separate Account Investment [Line Items]
Mortgage-backed securities	42,500
Investment Securities
Fair Value, Separate Account Investment [Line Items]
Accrued interest receivable	$ 6,300	$ 5,400

Amortized cost, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) and investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
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- Definition

The fair value as of the balance sheet date of firm holdings in mortgages, mortgage backed securities (investment instruments that represent ownership of an undivided interest in a group of mortgages, where principal and interest from the individual mortgages are used to pay investors' principal and interest on the mortgage backed security) and asset-backed securities that are primarily paid from the cash flows of a discrete pool of receivables or other financial assets (such as credit-card receivables), either fixed or revolving, that by their terms convert into cash within a finite time period. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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