Loans - Activity in the Allowance for Credit Losses (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, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 41,247	$ 41,648	$ 40,152	$ 40,161	$ 40,161
Charge-offs	(2,024)	(3,110)	(9,352)	(3,179)	(7,969)
Recoveries	934	74	1,286	231
Provision (benefit)	1,680	1,730	9,751	3,129
Ending balance	41,837	40,342	41,837	40,342	40,152
Multi-family residential
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	12,445	10,829	13,145	10,373	10,373
Charge-offs	(420)		(2,101)
Recoveries				1
Provision (benefit)	(50)	457	931	912
Ending balance	11,975	11,286	11,975	11,286	13,145
Commercial real estate
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	13,211	9,043	9,288	8,665	8,665
Charge-offs	(1,275)		(1,347)		(421)
Provision (benefit)	1,118	90	5,113	468
Ending balance	13,054	9,133	13,054	9,133	9,288
One-to-four family - mixed- use property
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,678	1,577	1,623	1,610	1,610
Charge-offs	(20)		(20)
Recoveries				2
Provision (benefit)	(102)	(46)	(47)	(81)
Ending balance	1,556	1,531	1,556	1,531	1,623
One-to-four family - residential
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	858	796	759	668	668
Charge-offs			(5)	(14)	(14)
Recoveries	48	58	53	61
Provision (benefit)	225	(46)	324	93
Ending balance	1,131	808	1,131	808	759
Construction loans
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	132	766	371	158	158
Provision (benefit)	19	(130)	(220)	478
Ending balance	151	636	151	636	371
Small Business Administration
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,366	1,126	1,523	1,626	1,626
Charge-offs	(277)	(7)	(279)	(7)	(7)
Recoveries	6	8	52	104
Provision (benefit)	(47)	302	(248)	(294)
Ending balance	1,048	1,429	1,048	1,429	1,523
Commercial business and other
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	11,557	17,511	13,443	17,061	17,061
Charge-offs	(32)	(3,103)	(5,600)	(3,158)
Recoveries	880	8	1,181	63
Provision (benefit)	517	1,103	3,898	1,553
Ending balance	$ 12,922	$ 15,519	$ 12,922	$ 15,519	$ 13,443

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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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 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

Reference 2: 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

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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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

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