BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Loans (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021	Mar. 11, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unamortized retained loan discounts	$ 9,800		$ 9,600
Loan receivable, nonaccrual, past due period (more than)	60 days
Loans receivable, impairment and (recovery) recorded	$ 0	$ 92
Loan loss reserves	980		943
PMC Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Acquisition discount	$ 330		$ 381	$ 33,900

Amount of unamortized discount of loans acquired in connection with business combinations in a disposal group.

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- Definition

Loan And Leases Receivable, Nonaccrual Loan And Lease Status, Past Due Period

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

+ References

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- Definition

Amount of unamortized purchase premium (discount) on financing receivable. Excludes financing receivable covered under loss sharing agreement.

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- Definition

Amount of credit loss expense (reversal of expense) for financing receivable.

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