FAIR VALUE MEASUREMENTS - Financial Instruments Disclosed, But Not Carried, at Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Amortized cost	$ 717,310	$ 698,351
Fair value	697,695	674,743
Federal Home Loan Bank advances	85,790	81,388
Federal Home Loan Bank advances, fair value	86,000	81,000
Reported value measurement
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Notes payable	1,313,000	1,312,000
Estimate of fair value measurement
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Notes payable	$ 1,160,000	$ 1,160,000

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Amount excluding accrued interest, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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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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No definition available.

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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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Fair value portion of notes payable.

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