Loans Receivable, Allowance for Credit Losses and Credit Quality - Change in the ACL (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Change in the ACL by major loan segment
Beginning balance	$ 42,601	$ 37,605	$ 37,857	$ 38,744	$ 32,222
Provision for (release of) credit losses	1,041		4,997	6,232	13,316
Charge offs	(693)	(844)	(5,305)	(3,441)	(8,191)
Recoveries of loans previously charged off	103		56	1,517	258
Ending balance	43,052	38,744	37,605	43,052	37,605
Residential real estate \| One to four-family residential
Change in the ACL by major loan segment
Beginning balance	1,288	1,171	1,960	1,195	1,835
Provision for (release of) credit losses	222		(789)	315	(664)
Ending balance	1,510	1,195	1,171	1,510	1,171
Residential real estate \| Home equity
Change in the ACL by major loan segment
Beginning balance	91	65	137	74	117
Provision for (release of) credit losses	33		(72)	50	(52)
Ending balance	124	74	65	124	65
Residential real estate \| Commercial real estate
Change in the ACL by major loan segment
Beginning balance	10,081	8,573	7,041	9,481	5,698
Provision for (release of) credit losses	(322)		5,532	(645)	6,875
Charge offs			(4,000)		(4,000)
Recoveries of loans previously charged off				923
Ending balance	9,759	9,481	8,573	9,759	8,573
Residential real estate \| Multi-family residential
Change in the ACL by major loan segment
Beginning balance	538	409	482	599	378
Provision for (release of) credit losses	65		(73)	4	31
Ending balance	603	599	409	603	409
Residential real estate \| Construction & Land Development
Change in the ACL by major loan segment
Beginning balance	7,153	4,297	6,436	4,137	7,630
Provision for (release of) credit losses	(1,165)		(2,139)	1,851	(3,333)
Ending balance	5,988	4,137	4,297	5,988	4,297
Commercial \| Commercial and industrial
Change in the ACL by major loan segment
Beginning balance	14,315	11,231	12,457	11,174	10,878
Provision for (release of) credit losses	174		(1,238)	3,291	684
Charge offs					(391)
Recoveries of loans previously charged off	12		12	36	60
Ending balance	14,501	11,174	11,231	14,501	11,231
Consumer
Change in the ACL by major loan segment
Beginning balance	9,135	11,859	9,344	12,084	5,686
Provision for (release of) credit losses	2,034		3,776	1,366	9,775
Charge offs	(693)	(844)	(1,305)	(3,441)	(3,800)
Recoveries of loans previously charged off	91		44	558	198
Ending balance	$ 10,567	$ 12,084	$ 11,859	$ 10,567	$ 11,859

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

Reference 1: 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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+ 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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+ References

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+ 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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+ 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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