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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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