Loans - Narrative (Details) $ in Thousands	12 Months Ended
Dec. 31, 2024 USD ($) loan	Dec. 31, 2023 USD ($) loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net deferred loan costs included in loan balances	$ 12,457	$ 11,479
Loans used to collateralize borrowings from the Federal Home Loan Bank of Boston	626,851	561,574
Loans to directors, officers and employees	54,997	54,425
Interest income which would have been recognized if interest had been accrued	172	142
Loans more than 90 days past due accruing interest	$ 1,020	$ 429
Number of mortgage loans in the process of foreclosure \| loan	3	5
Mortgage loans in the process of foreclosure	$ 192	$ 400
Interest rate swap agreements \| Designated as Hedging Instrument
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan adjustments	(560)	(1,769)
Interest rate swap agreements \| Fair Value Hedges \| Designated as Hedging Instrument
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan adjustments	(758)	(2,149)
Loans pledged as collateral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net loans	$ 392,562	$ 320,083

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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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