Loans Receivable - Activity in the allowance for credit losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Allowance for Credit Loss
Beginning balance	$ 2,817	$ 2,273	$ 2,682	$ 2,126
Provision	135	135	270	270
Recoveries		4		16
Ending balance	2,952	2,412	2,952	2,412
Residential \| One to Four Residential
Allowance for Credit Loss
Beginning balance	992	1,102	1,059	1,074
Provision	(24)	8	(91)	24
Recoveries		4		16
Ending balance	968	1,114	968	1,114
Residential \| Purchased and participations
Allowance for Credit Loss
Beginning balance	56	78	58	75
Provision	(1)	(9)	(3)	(6)
Ending balance	55	69	55	69
Residential \| Home improvement, first mortgage
Allowance for Credit Loss
Beginning balance	4	2	4	2
Ending balance	4	2	4	2
Residential \| HELOC
Allowance for Credit Loss
Beginning balance	58	52	53	52
Provision	8	(2)	13	(2)
Ending balance	66	50	66	50
Commercial \| Commercial construction
Allowance for Credit Loss
Beginning balance	456	238	448	195
Provision	45	109	53	152
Ending balance	501	347	501	347
Commercial \| Commercial and Industrial
Allowance for Credit Loss
Beginning balance	278	191	225	186
Provision	(8)	(40)	45	(35)
Ending balance	270	151	270	151
Commercial \| LOC
Allowance for Credit Loss
Beginning balance	40	115	94	107
Provision	141	(27)	87	(19)
Ending balance	181	88	181	88
Commercial Real Estate \| Commercial real estate
Allowance for Credit Loss
Beginning balance	933	495	741	435
Provision	(26)	96	166	156
Ending balance	$ 907	$ 591	$ 907	$ 591

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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- Definition

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

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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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
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-22

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