Loans - Activity in the Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 40,752	$ 38,729	$ 40,161	$ 40,442	$ 40,442
Charge-offs	(11)	(1,731)	(69)	(11,029)	(11,157)
Recoveries	103	171	157	235
Provision (benefit)	804	1,424	1,399	8,945
Ending balance	41,648	38,593	41,648	38,593	40,161
Multi-family Residential Portfolio Segment [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	10,590	9,041	10,373	9,552	9,552
Recoveries	1		1	1
Provision (benefit)	238	677	455	165
Ending balance	10,829	9,718	10,829	9,718	10,373
Commercial Real Estate [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	8,802	7,671	8,665	8,184	8,184
Charge-offs		(8)		(8)	(8)
Provision (benefit)	241	543	378	30
Ending balance	9,043	8,206	9,043	8,206	8,665
One-To-Four Family - Mixed-Use Property Portfolio Segment [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,583	1,710	1,610	1,875	1,875
Recoveries	2		2
Provision (benefit)	(8)	(95)	(35)	(260)
Ending balance	1,577	1,615	1,577	1,615	1,610
One-To-Four Family - Residential Portfolio Segment [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	849	727	668	901	901
Charge-offs		(6)	(14)	(12)	(23)
Recoveries	2	2	3	44
Provision (benefit)	(55)	(69)	139	(279)
Ending balance	796	654	796	654	668
Construction Portfolio Segment
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	156	152	158	261	261
Provision (benefit)	610	(20)	608	(129)
Ending balance	766	132	766	132	158
Small Business Administration Portfolio Segment [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,406	2,169	1,626	2,198	2,198
Charge-offs		(1)		(7)	(7)
Recoveries	91	159	96	171
Provision (benefit)	(371)	(165)	(596)	(200)
Ending balance	1,126	2,162	1,126	2,162	1,626
Commercial Business and Other Portfolio Segment [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	17,366	17,259	17,061	17,471	17,471
Charge-offs	(11)	(1,716)	(55)	(11,002)
Recoveries	7	10	55	19
Provision (benefit)	149	553	450	9,618
Ending balance	$ 17,511	$ 16,106	$ 17,511	$ 16,106	$ 17,061

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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