Loans - Activity in the Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 41,648	$ 38,593	$ 40,161	$ 40,442	$ 40,442
Charge-offs	(3,110)	(21)	(3,179)	(11,050)	(11,157)
Recoveries	74	63	231	298
Provision (benefit)	1,730	593	3,129	9,538
Ending balance	40,342	39,228	40,342	39,228	40,161
Multi-family Residential Portfolio Segment [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	10,829	9,718	10,373	9,552	9,552
Recoveries			1	1
Provision (benefit)	457	917	912	1,082
Ending balance	11,286	10,635	11,286	10,635	10,373
Commercial Real Estate [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	9,043	8,206	8,665	8,184	8,184
Charge-offs				(8)	(8)
Provision (benefit)	90	562	468	592
Ending balance	9,133	8,768	9,133	8,768	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	1,577	1,615	1,610	1,875	1,875
Recoveries			2
Provision (benefit)	(46)	10	(81)	(250)
Ending balance	1,531	1,625	1,531	1,625	1,610
One-To-Four Family - Residential Portfolio Segment [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	796	654	668	901	901
Charge-offs			(14)	(12)	(23)
Recoveries	58	6	61	50
Provision (benefit)	(46)	57	93	(222)
Ending balance	808	717	808	717	668
Construction Portfolio Segment
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	766	132	158	261	261
Provision (benefit)	(130)	32	478	(97)
Ending balance	636	164	636	164	158
Small Business Administration Portfolio Segment [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,126	2,162	1,626	2,198	2,198
Charge-offs	(7)		(7)	(7)	(7)
Recoveries	8	48	104	219
Provision (benefit)	302	(194)	(294)	(394)
Ending balance	1,429	2,016	1,429	2,016	1,626
Commercial Business and Other Portfolio Segment [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	17,511	16,106	17,061	17,471	17,471
Charge-offs	(3,103)	(21)	(3,158)	(11,023)
Recoveries	8	9	63	28
Provision (benefit)	1,103	(791)	1,553	8,827
Ending balance	$ 15,519	$ 15,303	$ 15,519	$ 15,303	$ 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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