FAIR VALUE MEASUREMENTS - Unobservable Inputs Non-recurring (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2025	Dec. 31, 2024
Fair Value Measurement Inputs and Valuation Techniques [Line Items}
Fair value	$ 597,810	$ 521,018
Non-recurring \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items}
Individually evaluated loans	2,697	3,224
Capitalized servicing rights	7,021	7,285
Premises held for sale		419
Total	9,718	10,928
Non-recurring \| Level 3 \| Quoted prices for similar loans in active markets
Fair Value Measurement Inputs and Valuation Techniques [Line Items}
Individually evaluated loans	1,914	2,733
Non-recurring \| Level 3 \| Discount Cash Flows
Fair Value Measurement Inputs and Valuation Techniques [Line Items}
Individually evaluated loans	$ 783	$ 491
Non-recurring \| Level 3 \| Impaired loans \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items}
Loss severity	10.00%	10.00%
Appraised value	$ 75	$ 257
Discount rate	4.00%	4.00%
Cash Flows	$ 370	$ 497
Non-recurring \| Level 3 \| Impaired loans \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items}
Loss severity	75.00%	65.00%
Appraised value	$ 852	$ 1,260
Discount rate	6.06%	4.99%
Cash Flows	$ 489	$ 501
Non-recurring \| Level 3 \| Capitalized servicing rights
Fair Value Measurement Inputs and Valuation Techniques [Line Items}
Constant prepayment rate	8.05%	6.52%
Discount rate	9.62%	10.06%
Non-recurring \| Level 3 \| Assets held for sale
Fair Value Measurement Inputs and Valuation Techniques [Line Items}
Premises held for sale	$ 0	$ 419
Appraised value	$ 0	$ 440
Selling Costs	5.00%	5.00%

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Fair Value Inputs, Cash Flow

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Fair Value Inputs, Selling Costs

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Fair value portion of asset recognized for present right to economic benefit.

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Fair value portion of assets classified as held for sale.

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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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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Amount of financing receivable individually evaluated for credit loss. Excludes financing receivable collectively evaluated for credit loss.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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Discount rate used to estimate the fair value of servicing assets and servicing liabilities.

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Percentage of contractually collectible principal associated with a financial asset expected not to be collected due to default by the borrower.

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Estimated rate of prepayments of principal on servicing assets and servicing liabilities.

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