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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%

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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 470 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478878/942-470-45-1 + Details
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- Definition Amount of advance from Federal Home Loan Bank (FHLBank). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 470 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478878/942-470-45-1 + Details
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- Definition Rate of interest applicable on advance from Federal Home Loan Bank (FHLBank). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 470 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478878/942-470-45-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477734/942-470-50-3 + Details
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- Definition Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(13)(3)(a)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 470 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478878/942-470-45-1 + Details
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