Loans - Activity in the Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 42,802	$ 40,152	$ 40,152
Charge-offs	(1,052)	(4,471)	(11,403)
Recoveries	532	44
Provision (benefit)	2,168	4,312
Ending balance	44,450	40,037	42,802
Multi-family residential
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	12,601	13,145	13,145
Charge-offs	(173)		(2,935)
Recoveries	1
Provision (benefit)	683	(573)
Ending balance	13,112	12,572	12,601
Commercial real estate
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	13,559	9,288	9,288
Charge-offs	(616)		(1,347)
Provision (benefit)	399	3,694
Ending balance	13,342	12,982	13,559
One-to-four family - mixed- use property
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,236	1,623	1,623
Charge-offs			(55)
Provision (benefit)	3	79
Ending balance	1,239	1,702	1,236
One-to-four family - residential
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	875	759	759
Charge-offs	(147)	(5)	(5)
Recoveries		1
Provision (benefit)	101	164
Ending balance	829	919	875
Construction loans
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	171	371	371
Provision (benefit)	(43)	(171)
Ending balance	128	200	171
Small Business Administration
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,881	1,523	1,523
Charge-offs			(279)
Recoveries		40
Provision (benefit)	283	(362)
Ending balance	2,164	1,201	1,881
Commercial business and other
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	12,479	13,443	13,443
Charge-offs	(116)	(4,466)
Recoveries	531	3
Provision (benefit)	742	1,481
Ending balance	$ 13,636	$ 10,461	$ 12,479

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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