LOANS AND ALLOWANCE FOR CREDIT LOSSES - Narrative (Details) - USD ($)	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrued interest receivable on loans	$ 8,900,000	$ 8,000,000.0
Deferred loan costs, net	4,100,000	4,700,000
Loans, net of deferred loan fees	2,269,561,000	2,071,419,000
Residential mortgages held for sale	0	0
Transfer of portfolio loans to loans held for sale	2,064,000	0
Loans individually analyzed	$ 4,187,000	6,471,000
Number of days past due after which a retail loan is rated	90 days
Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans individually analyzed	$ 2,173,000	5,089,000
Commercial Mortgages, Other Loan Category
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of deferred loan fees	1,290,000,000	1,120,000,000
Residential Mortgages and Home Equity Loans \| Asset Pledged as Collateral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial instruments, owned, at fair value	255,100,000	$ 244,600,000
Commercial Credit Card
Accounts, Notes, Loans and Financing Receivable [Line Items]
Transfer of portfolio loans to loans held for sale	$ 2,100,000

Number Of Days Past Due After Which A Loan Will Be Rated

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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, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The aggregate fair value as of the balance sheet date of financial instruments and other positions owned by the entity including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities. Includes both pledged and unpledged holdings.

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Amount, before allowance for credit loss, of accrued interest on financing receivable.

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

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Amount, after valuation allowance, of financing receivable held for sale and not part of disposal group. Excludes loan covered under loss sharing agreement and loan classified as investment in debt security.

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Value of loans and leases held in the entity's portfolio transferred to loans and leases held-for-sale in noncash transactions.

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