ALLOWANCE FOR CREDIT LOSSES - Summary of loans by portfolio segment evaluated for impairment (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Loans
Individually Evaluated	$ 6,840	$ 11,657
Collectively Evaluated	1,579,220	1,533,470
Total	1,586,060	1,545,127
Allowance for Credit Losses on Loans
Individually Evaluated	0	27
Collectively Evaluated	14,153	13,373
Total	14,153	13,400
Residential Portfolio Segment \| Residential one-to-four family
Loans
Individually Evaluated	6,672	8,418
Collectively Evaluated	586,137	588,836
Total	592,809	597,254
Allowance for Credit Losses on Loans
Individually Evaluated	0	27
Collectively Evaluated	2,275	2,237
Total	2,275	2,264
Residential Portfolio Segment \| Multifamily
Loans
Individually Evaluated	168	516
Collectively Evaluated	695,039	690,174
Total	695,207	690,690
Allowance for Credit Losses on Loans
Individually Evaluated	0	0
Collectively Evaluated	6,146	5,491
Total	6,146	5,491
Nonresidential Portfolio Segment \| Non-residential
Loans
Individually Evaluated	0	2,671
Collectively Evaluated	239,844	213,390
Total	239,844	216,061
Allowance for Credit Losses on Loans
Individually Evaluated	0	0
Collectively Evaluated	4,565	3,357
Total	4,565	3,357
Commercial Portfolio Segment \| Construction
Loans
Individually Evaluated	0	0
Collectively Evaluated	28,141	17,799
Total	28,141	17,799
Allowance for Credit Losses on Loans
Individually Evaluated	0	0
Collectively Evaluated	1,048	1,697
Total	1,048	1,697
Commercial and industrial (including PPP) \| Commercial and industrial (including PPP)
Loans
Individually Evaluated	0	0
Collectively Evaluated	10,357	4,653
Total	10,357	4,653
Allowance for Credit Losses on Loans
Individually Evaluated	0	0
Collectively Evaluated	32	47
Total	32	47
Junior Lien Portfolio Segment \| Junior liens
Loans
Individually Evaluated	0	52
Collectively Evaluated	19,644	18,579
Total	19,644	18,631
Allowance for Credit Losses on Loans
Individually Evaluated	0	0
Collectively Evaluated	87	451
Total	87	451
Consumer Portfolio Segment \| Consumer and other
Loans
Individually Evaluated	0	0
Collectively Evaluated	58	39
Total	58	39
Allowance for Credit Losses on Loans
Individually Evaluated	0	0
Collectively Evaluated	0	0
Total	0	0
Unallocated Financing Receivables
Loans
Individually Evaluated	0	0
Collectively Evaluated	0	0
Total	0	0
Allowance for Credit Losses on Loans
Individually Evaluated	0	0
Collectively Evaluated	0	93
Total	$ 0	$ 93

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