Loans - Narrative (Details) $ in Thousands	Jun. 30, 2025 USD ($) loan	Dec. 31, 2024 USD ($) loan	Jun. 30, 2024 USD ($) loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net deferred loan costs	$ 12,821	$ 12,457	$ 12,130
Loans used to collateralize borrowings from the Federal Home Loan Bank of Boston	603,943	626,851	624,058
Loans	$ 2,394,007	$ 2,340,940	$ 2,247,670
Number of mortgage loans in the process of foreclosure \| loan	2	3	2
Mortgage loans in the process of foreclosure	$ 859	$ 192	$ 127
Asset Pledged as Collateral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	384,083	392,562	353,650
Interest rate swap agreements \| Designated as Hedging Instrument
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan adjustments	(897)	(560)	996
Interest rate swap agreements \| Fair Value Hedging \| Designated as Hedging Instrument
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan adjustments	$ (1,003)	$ (758)	$ 68

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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Amount of fee received for commitment to originate or purchase financing receivable where likelihood of commitment being exercised is remote, to be recognized as service income.

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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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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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