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Loans and Allowance for Credit Losses on Loans - Transactions In The Allowance For Loan Losses ("ALL") (Detail) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Balance | $ 3,517 | $ 3,451 | $ 3,486 | $ 3,390
(Release) provision for credit losses on loans |  | 20 | 30 | 80
Charge-offs |  | (27) |  | (27)
Recoveries |  | 1 | 1 | 2
Balance | 3,517 | 3,445 | 3,517 | 3,445
CRE [Member] |  |  |  |
Balance | 654 | 745 | 710 | 830
(Release) provision for credit losses on loans | 9 | (25) | (47) | (110)
Balance | 663 | 720 | 663 | 720
MF [Member] |  |  |  |
Balance | 57 | 107 | 59 | 76
(Release) provision for credit losses on loans | (10) | (47) | (12) | (16)
Balance | 47 | 60 | 47 | 60
C+I [Member] |  |  |  |
Balance | 202 | 234 | 233 | 236
(Release) provision for credit losses on loans | (3) | 3 | (34) | 1
Balance | 199 | 237 | 199 | 237
ADL [Member] |  |  |  |
Balance | 92 | 70 | 87 | 105
(Release) provision for credit losses on loans | (2) | 8 | 3 | (27)
Balance | 90 | 78 | 90 | 78
RES [Member] |  |  |  |
Balance | 1,560 | 1,608 | 1,612 | 1,601
(Release) provision for credit losses on loans | (32) | 44 | (84) | 51
Balance | 1,528 | 1,652 | 1,528 | 1,652
HELOC [Member] |  |  |  |
Balance | 237 | 171 | 214 | 156
(Release) provision for credit losses on loans | 1 | 3 | 24 | 18
Balance | 238 | 174 | 238 | 174
CON [Member] |  |  |  |
Balance | 542 | 442 | 439 | 357
(Release) provision for credit losses on loans | (24) | 61 | 78 | 145
Charge-offs |  | (27) |  | (27)
Recoveries |  | 1 | 1 | 2
Balance | 518 | 477 | 518 | 477
Unallocated [Member] |  |  |  |
Balance | 173 | 74 | 132 | 29
(Release) provision for credit losses on loans | 61 | (27) | 102 | 18
Balance | $ 234 | $ 47 | $ 234 | $ 47

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