Loans held for sale - Delinquent and Non-performing Loans Sold During the Period Indicated (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025 USD ($) loan	Jun. 30, 2024 USD ($) loan	Jun. 30, 2025 USD ($) loan	Jun. 30, 2024 USD ($) loan
Nonperforming Financial Instruments [Member]
Loans sold \| loan	4	2	7	11
Proceeds	$ 12,894	$ 690	$ 18,679	$ 4,500
Net Charge-offs	(1,681)		(1,681)
Net gain	$ 68	$ 26	$ 459	$ 136
Nonperforming Financial Instruments [Member] \| Multi-family Residential Portfolio Segment [Member]
Loans sold \| loan	4	1	5	4
Proceeds	$ 12,894	$ 432	$ 13,444	$ 1,984
Net Charge-offs	(1,681)		(1,681)
Net gain	$ 68		$ 202	$ 55
Nonperforming Financial Instruments [Member] \| Commercial Real Estate
Loans sold \| loan			1	2
Proceeds			$ 5,098	$ 970
Net gain			$ 238
Nonperforming Financial Instruments [Member] \| One-To-Four Family - Mixed-Use Property Portfolio Segment [Member]
Loans sold \| loan		1	1	5
Proceeds		$ 258	$ 137	$ 1,546
Net gain		$ 26	$ 19	$ 81
Performing Financial Instruments [Member]
Loans sold \| loan	2		19
Proceeds	$ 1,025		$ 43,670
Net gain	$ 98		$ 532
Performing Financial Instruments [Member] \| Multi-family Residential Portfolio Segment [Member]
Loans sold \| loan			12
Proceeds			$ 33,721
Performing Financial Instruments [Member] \| Commercial Real Estate
Loans sold \| loan			1
Proceeds			$ 3,120
Performing Financial Instruments [Member] \| Small Business Administration Portfolio Segment [Member]
Loans sold \| loan	2		6
Proceeds	$ 1,025		$ 6,829
Net gain	$ 98		$ 532