Investment Securities - Additional Information (Details) - USD ($)	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Debt Securities, Available-for-Sale [Line Items]
Securities available-for-sale, allowance for credit loss	$ 0	$ 0
Securities, held to maturity, allowance for credit losses	0
Proceeds from sales of securities available for sale	9,600,000	51,900,000
Gross realized losses	837,000	4,200,000
Gross realized gains	0	3,000
Equity securities	0
Equity securities and recognized gains		2,600,000
Federal Reserve Bank of Boston Discount Window
Debt Securities, Available-for-Sale [Line Items]
Carrying value of investment securities pledged as collateral	78,500,000	86,300,000
Federal Home Loan Bank
Debt Securities, Available-for-Sale [Line Items]
Carrying value of investment securities pledged as collateral	$ 188,700,000	$ 196,500,000

Carrying value of investment securities pledged as collateral.

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Amount of allowance for credit loss on 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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