Borrowings - Additional Information (Detail) - USD ($) $ in Thousands	Sep. 30, 2025	Jan. 07, 2025	Dec. 31, 2024
Banks unused remaining borrowing capacity	$ 98,700		$ 94,000
Advances through FLHB	51,748		52,268
Federal home loan bank maximum borrowing capacity	3,000		3,000
Fed Funds Borrowing [Member]
Fed funds borrowing capacity	2,000		2,000
Borrower-In-Custody of Collateral Program [Member]
Banks unused remaining borrowing capacity	37,600		37,600
Collateral pledged		$ 65,000
New England Program [Member]
Advances through FLHB	$ 1,700		$ 2,300
Interest rate	0.00%		0.00%
FHLB Callable Date October 29, 2025 [Member]
FHLB loan borrowed	$ 25,000		$ 25,000
Interest rate	4.75%		4.75%
FHLB Callable Date December 8, 2025 [Member]
FHLB loan borrowed	$ 25,000		$ 25,000
Interest rate	4.38%		4.38%

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Amount of advance from Federal Home Loan Bank (FHLBank).

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Rate of interest applicable on advance from Federal Home Loan Bank (FHLBank).

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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

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

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Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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