LOANS AND ALLOWANCE FOR CREDIT LOSSES - Non Traditional Mortgage Loans Additional Information (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 7,156,206	$ 7,115,038
NTM Loans \| Loan Portfolio \| Loan Portfolio Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage to total loans and leases (percent)	11.30%	12.10%
NTM Loans \| Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 811,700	$ 862,300
Decrease in Non-Traditional Mortgage portfolio loans	50,700
NTM Loans \| Consumer \| Non-performing Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 13,300	$ 3,000
Weighted average LTV (percent)	61.00%
NTM Loans \| Consumer \| Interest Only \| Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loan term (in years)	40 years
Mortgage loan, flexible initial term (in years)	10 years
NTM Loans \| Consumer \| Interest Only \| Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loan, flexible initial term (in years)	1 year
NTM Loans \| Consumer \| Loan Portfolio \| Loan Portfolio Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Decrease in Non-Traditional Mortgage portfolio loans (percent)	5.90%

Financing Receivable, Excluding Accrued Interest, Increase (Decrease)

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Financing Receivable, Excluding Accrued Interest, Increase (Decrease), Percentage

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Financing Receivable, Mortgage Loan, Flexible Initial Term

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Financing Receivable, Mortgage Loan, Term

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Non-Traditional Mortgage Performance Indicators, Weighted Average Loan To Value ratio, Percentage

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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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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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

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