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	6 Months Ended	12 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	$ 8,071	$ 8,110	$ 8,407	$ 7,680	$ 7,680
Charge-Offs	0	0	0	(4)	(47)
Recoveries	4	5	8	10
Credit Loss Expense (Benefit)	315	192	(25)	621
Balance end of period	8,390	8,307	8,390	8,307	8,407
Residential real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	3,009	3,066	3,176	3,492	3,492
Charge-Offs	0	0	0	0
Recoveries	4	4	7	9
Credit Loss Expense (Benefit)	89	65	(81)	(366)
Balance end of period	3,102	3,135	3,102	3,135	3,176
Residential real estate \| Non-revolving residential real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	2,753	2,866	2,913	3,212	3,212
Charge-Offs	0	0	0	0	0
Recoveries	4	4	7	9
Credit Loss Expense (Benefit)	67	35	(96)	(316)
Balance end of period	2,824	2,905	2,824	2,905	2,913
Residential real estate \| Revolving residential real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	256	200	263	280	280
Charge-Offs	0	0	0	0	0
Recoveries	0	0	0	0
Credit Loss Expense (Benefit)	22	30	15	(50)
Balance end of period	278	230	278	230	263
Construction real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	707	1,018	840	753	753
Charge-Offs	0	0	0	0
Recoveries	0	0	0	0
Credit Loss Expense (Benefit)	34	220	(99)	485
Balance end of period	741	1,238	741	1,238	840
Construction real estate \| Commercial construction real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	585	822	654	651	651
Charge-Offs	0	0	0	0	0
Recoveries	0	0	0	0
Credit Loss Expense (Benefit)	35	197	(34)	368
Balance end of period	620	1,019	620	1,019	654
Construction real estate \| Residential construction real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	122	196	186	102	102
Charge-Offs	0	0	0	0	0
Recoveries	0	0	0	0
Credit Loss Expense (Benefit)	(1)	23	(65)	117
Balance end of period	121	219	121	219	186
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	4,020	3,513	3,994	2,978	2,978
Charge-Offs	0	0	0	0
Recoveries	0	0	0	0
Credit Loss Expense (Benefit)	248	(55)	274	480
Balance end of period	4,268	3,458	4,268	3,458	3,994
Commercial real estate \| Non-residential commercial real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	3,759	3,255	3,755	2,766	2,766
Charge-Offs	0	0	0	0	0
Recoveries	0	0	0	0
Credit Loss Expense (Benefit)	252	(55)	256	434
Balance end of period	4,011	3,200	4,011	3,200	3,755
Commercial real estate \| Multi-family residential real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	261	258	239	212	212
Charge-Offs	0	0	0	0	0
Recoveries	0	0	0	0
Credit Loss Expense (Benefit)	(4)	0	18	46
Balance end of period	257	258	257	258	239
Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	241	427	292	377	377
Charge-Offs	0	0	0	0	(41)
Recoveries	0	0	1	0
Credit Loss Expense (Benefit)	3	12	(49)	62
Balance end of period	244	439	244	439	292
Consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	3	7	5	6	6
Charge-Offs	0	0	0	(4)	(6)
Recoveries	0	1	0	1
Credit Loss Expense (Benefit)	(1)	(2)	(3)	3
Balance end of period	2	6	2	6	5
Municipal
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance beginning of period	91	79	100	74	74
Charge-Offs	0	0	0	0	0
Recoveries	0	0	0	0
Credit Loss Expense (Benefit)	(58)	(48)	(67)	(43)
Balance end of period	$ 33	$ 31	$ 33	$ 31	$ 100

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477657/942-210-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478478/942-210-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(7)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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- Definition

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

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- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
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