Loans - Activity in the Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 40,161	$ 40,442	$ 40,442
Charge-offs	(58)	(9,298)	(11,157)
Recoveries	54	64
Provision (benefit)	595	7,521
Ending balance	40,752	38,729	40,161
Multi-family Residential Portfolio Segment [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	10,373	9,552	9,552
Recoveries		1
Provision (benefit)	217	(512)
Ending balance	10,590	9,041	10,373
Commercial Real Estate [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	8,665	8,184	8,184
Charge-offs			(8)
Provision (benefit)	137	(513)
Ending balance	8,802	7,671	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	1,610	1,875	1,875
Provision (benefit)	(27)	(165)
Ending balance	1,583	1,710	1,610
One-To-Four Family - Residential Portfolio Segment [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	668	901	901
Charge-offs	(14)	(6)	(23)
Recoveries	1	42
Provision (benefit)	194	(210)
Ending balance	849	727	668
Construction Portfolio Segment
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	158	261	261
Provision (benefit)	(2)	(109)
Ending balance	156	152	158
Small Business Administration Portfolio Segment [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,626	2,198	2,198
Charge-offs		(6)	(7)
Recoveries	5	12
Provision (benefit)	(225)	(35)
Ending balance	1,406	2,169	1,626
Commercial Business and Other Portfolio Segment [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	17,061	17,471	17,471
Charge-offs	(44)	(9,286)
Recoveries	48	9
Provision (benefit)	301	9,065
Ending balance	$ 17,366	$ 17,259	$ 17,061