ALLOWANCE FOR CREDIT LOSSES - Summary of loans by portfolio segment evaluated for impairment (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Loans
Individually Evaluated	$ 7,695	$ 11,657
Collectively Evaluated	1,574,050	1,533,470
Total	1,581,745	1,545,127
Allowance for Credit Losses on Loans
Individually Evaluated	0	27
Collectively Evaluated	14,413	13,373
Total	14,413	13,400
Residential Portfolio Segment \| Residential one-to-four family
Loans
Individually Evaluated	7,484	8,418
Collectively Evaluated	572,912	588,836
Total	580,396	597,254
Allowance for Credit Losses on Loans
Individually Evaluated	0	27
Collectively Evaluated	1,994	2,237
Total	1,994	2,264
Residential Portfolio Segment \| Multifamily
Loans
Individually Evaluated	160	516
Collectively Evaluated	696,796	690,174
Total	696,956	690,690
Allowance for Credit Losses on Loans
Individually Evaluated	0	0
Collectively Evaluated	7,017	5,491
Total	7,017	5,491
Nonresidential Portfolio Segment \| Non-residential
Loans
Individually Evaluated	0	2,671
Collectively Evaluated	237,247	213,390
Total	237,247	216,061
Allowance for Credit Losses on Loans
Individually Evaluated	0	0
Collectively Evaluated	3,813	3,357
Total	3,813	3,357
Commercial Portfolio Segment \| Construction
Loans
Individually Evaluated	0	0
Collectively Evaluated	36,032	17,799
Total	36,032	17,799
Allowance for Credit Losses on Loans
Individually Evaluated	0	0
Collectively Evaluated	1,428	1,697
Total	1,428	1,697
Commercial and industrial \| Commercial and industrial
Loans
Individually Evaluated	0	0
Collectively Evaluated	9,743	4,653
Total	9,743	4,653
Allowance for Credit Losses on Loans
Individually Evaluated	0	0
Collectively Evaluated	111	47
Total	111	47
Junior Lien Portfolio Segment \| Junior liens
Loans
Individually Evaluated	51	52
Collectively Evaluated	21,287	18,579
Total	21,338	18,631
Allowance for Credit Losses on Loans
Individually Evaluated	0	0
Collectively Evaluated	50	451
Total	50	451
Consumer Portfolio Segment \| Consumer and other
Loans
Individually Evaluated	0	0
Collectively Evaluated	33	39
Total	33	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
Collectively Evaluated		0
Total		0
Allowance for Credit Losses on Loans
Individually Evaluated		0
Collectively Evaluated		93
Total		$ 93

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