Allowance for Credit Losses on Loans and Off-Balance Sheet Credit Exposures - Schedule of Allowance For Loan Losses, By Class (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	$ 8,307	$ 6,893	$ 7,680	$ 6,566	$ 6,566
Charge-Offs	(42)	(1)	(46)	(2)	(3)
Recoveries	5	6	15	18
Credit Loss Expense (Benefit)	127	468	748	784
Balance end of period	8,397	7,366	8,397	7,366	7,680
Residential real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	3,135	3,240	3,492	2,520	2,520
Charge-Offs	0	0	0	0
Recoveries	3	6	12	17
Credit Loss Expense (Benefit)	10	100	(356)	809
Balance end of period	3,148	3,346	3,148	3,346	3,492
Residential real estate | Non-revolving residential real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	2,905	2,967	3,212	2,361	2,361
Charge-Offs	0	0	0	0	0
Recoveries	3	6	12	17
Credit Loss Expense (Benefit)	(11)	100	(327)	695
Balance end of period	2,897	3,073	2,897	3,073	3,212
Residential real estate | Revolving residential real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	230	273	280	159	159
Charge-Offs	0	0	0	0	0
Recoveries	0	0	0	0
Credit Loss Expense (Benefit)	21	0	(29)	114
Balance end of period	251	273	251	273	280
Construction real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	1,238	632	753	1,198	1,198
Charge-Offs	0	0	0	0
Recoveries	0	0	0	0
Credit Loss Expense (Benefit)	86	151	571	(415)
Balance end of period	1,324	783	1,324	783	753
Construction real estate | Commercial construction real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	1,019	544	651	1,035	1,035
Charge-Offs	0	0	0	0	0
Recoveries	0	0	0	0
Credit Loss Expense (Benefit)	103	140	471	(351)
Balance end of period	1,122	684	1,122	684	651
Construction real estate | Residential construction real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	219	88	102	163	163
Charge-Offs	0	0	0	0	0
Recoveries	0	0	0	0
Credit Loss Expense (Benefit)	(17)	11	100	(64)
Balance end of period	202	99	202	99	102
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	3,458	2,676	2,978	2,426	2,426
Charge-Offs	0	0	0	0
Recoveries	0	0	0	0
Credit Loss Expense (Benefit)	43	175	523	425
Balance end of period	3,501	2,851	3,501	2,851	2,978
Commercial real estate | Non-residential commercial real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	3,200	2,469	2,766	2,182	2,182
Charge-Offs	0	0	0	0	0
Recoveries	0	0	0	0
Credit Loss Expense (Benefit)	53	173	487	460
Balance end of period	3,253	2,642	3,253	2,642	2,766
Commercial real estate | Multi-family residential real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	258	207	212	244	244
Charge-Offs	0	0	0	0	0
Recoveries	0	0	0	0
Credit Loss Expense (Benefit)	(10)	2	36	(35)
Balance end of period	248	209	248	209	212
Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	439	312	377	352	352
Charge-Offs	(41)	0	(41)	0	0
Recoveries	2	0	2	1
Credit Loss Expense (Benefit)	(89)	(14)	(27)	(55)
Balance end of period	311	298	311	298	377
Consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	6	7	6	5	5
Charge-Offs	(1)	(1)	(5)	(2)	(3)
Recoveries	0	0	1	0
Credit Loss Expense (Benefit)	0	0	3	3
Balance end of period	5	6	5	6	6
Municipal
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	31	26	74	65	65
Charge-Offs	0	0	0	0	0
Recoveries	0	0	0	0
Credit Loss Expense (Benefit)	77	56	34	17
Balance end of period	$ 108	$ 82	$ 108	$ 82	$ 74