LOANS RECEIVABLE - Credit quality indicators (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Loan origination, year one	$ 26,009	$ 92,329
Loan origination, year two	95,541	524,566
Loan origination, year three	526,152	304,995
Loan origination, year four	292,022	65,175
Loan origination, year five	64,202	82,358
Loan origination, more than five years	543,430	491,285
Revolving Loans	28	22
Total	1,547,384	1,560,730
Residential Portfolio Segment \| Residential
Financing Receivable, Credit Quality Indicator [Line Items]
Loan origination, year one	2,034	13,338
Loan origination, year two	13,149	98,007
Loan origination, year three	95,083	109,193
Loan origination, year four	105,468	14,315
Loan origination, year five	14,079	18,460
Loan origination, more than five years	296,640	297,616
Revolving Loans	0	0
Total	526,453	550,929
Residential Portfolio Segment \| Residential \| Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loan origination, year one	2,034	13,338
Loan origination, year two	13,149	98,007
Loan origination, year three	95,083	109,193
Loan origination, year four	105,468	14,315
Loan origination, year five	14,079	18,460
Loan origination, more than five years	290,729	291,069
Revolving Loans	0	0
Total	520,542	544,382
Residential Portfolio Segment \| Residential \| Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loan origination, year one	0	0
Loan origination, year two	0	0
Loan origination, year three	0	0
Loan origination, year four	0	0
Loan origination, year five	0	0
Loan origination, more than five years	653	663
Revolving Loans	0	0
Total	653	663
Residential Portfolio Segment \| Residential \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loan origination, year one	0	0
Loan origination, year two	0	0
Loan origination, year three	0	0
Loan origination, year four	0	0
Loan origination, year five	0	0
Loan origination, more than five years	5,258	5,884
Revolving Loans	0	0
Total	5,258	5,884
Residential Portfolio Segment \| Multifamily
Financing Receivable, Credit Quality Indicator [Line Items]
Loan origination, year one	4,320	17,144
Loan origination, year two	17,041	281,906
Loan origination, year three	280,383	158,705
Loan origination, year four	151,617	35,407
Loan origination, year five	35,022	56,739
Loan origination, more than five years	182,802	132,663
Revolving Loans	0	0
Total	671,185	682,564
Residential Portfolio Segment \| Multifamily \| Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loan origination, year one	4,320	17,144
Loan origination, year two	17,041	281,906
Loan origination, year three	280,383	158,705
Loan origination, year four	151,617	35,407
Loan origination, year five	35,022	56,739
Loan origination, more than five years	182,670	132,517
Revolving Loans	0	0
Total	671,053	682,418
Residential Portfolio Segment \| Multifamily \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loan origination, year one	0	0
Loan origination, year two	0	0
Loan origination, year three	0	0
Loan origination, year four	0	0
Loan origination, year five	0	0
Loan origination, more than five years	132	146
Revolving Loans	0	0
Total	132	146
Commercial Real Estate Portfolio Segment \| Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Loan origination, year one	13,744	26,610
Loan origination, year two	26,624	118,247
Loan origination, year three	117,088	14,785
Loan origination, year four	14,638	15,080
Loan origination, year five	14,859	5,386
Loan origination, more than five years	54,914	52,397
Revolving Loans	0	0
Total	241,867	232,505
Commercial Real Estate Portfolio Segment \| Commercial real estate \| Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loan origination, year one	13,744	26,610
Loan origination, year two	26,624	118,247
Loan origination, year three	117,088	14,785
Loan origination, year four	14,638	15,080
Loan origination, year five	14,859	5,386
Loan origination, more than five years	54,048	51,493
Revolving Loans	0	0
Total	241,001	231,601
Commercial Real Estate Portfolio Segment \| Commercial real estate \| Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loan origination, year one	0	0
Loan origination, year two	0	0
Loan origination, year three	0	0
Loan origination, year four	0	0
Loan origination, year five	0	0
Loan origination, more than five years	866	904
Revolving Loans	0	0
Total	866	904
Construction and Land Portfolio Segment \| Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Loan origination, year one	0	22,798
Loan origination, year two	26,025	21,067
Loan origination, year three	28,373	16,549
Loan origination, year four	17,484	0
Loan origination, year five	0	0
Loan origination, more than five years	0	0
Revolving Loans	0	0
Total	71,882	60,414
Construction and Land Portfolio Segment \| Construction \| Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loan origination, year one	0	22,798
Loan origination, year two	26,025	21,067
Loan origination, year three	28,373	16,549
Loan origination, year four	17,484	0
Loan origination, year five	0	0
Loan origination, more than five years	0	0
Revolving Loans	0	0
Total	71,882	60,414
Junior Lien Portfolio Segment \| Junior liens
Financing Receivable, Credit Quality Indicator [Line Items]
Loan origination, year one	2,235	5,359
Loan origination, year two	5,734	5,234
Loan origination, year three	5,125	1,232
Loan origination, year four	1,243	296
Loan origination, year five	242	1,773
Loan origination, more than five years	9,074	8,609
Revolving Loans	0	0
Total	23,653	22,503
Junior Lien Portfolio Segment \| Junior liens \| Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loan origination, year one	2,235	5,359
Loan origination, year two	5,734	5,234
Loan origination, year three	5,125	1,232
Loan origination, year four	1,243	296
Loan origination, year five	242	1,773
Loan origination, more than five years	9,027	8,560
Revolving Loans	0	0
Total	23,606	22,454
Junior Lien Portfolio Segment \| Junior liens \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loan origination, year one	0	0
Loan origination, year two	0	0
Loan origination, year three	0	0
Loan origination, year four	0	0
Loan origination, year five	0	0
Loan origination, more than five years	47	49
Revolving Loans	0	0
Total	47	49
Commercial Portfolio Segment \| Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Loan origination, year one	3,621	7,055
Loan origination, year two	6,968	105
Loan origination, year three	100	4,531
Loan origination, year four	1,572	77
Loan origination, year five	0	0
Loan origination, more than five years	0	0
Revolving Loans	0	0
Total	12,261	11,768
Commercial Portfolio Segment \| Commercial and industrial \| Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loan origination, year one	3,621	7,055
Loan origination, year two	6,212	105
Loan origination, year three	100	4,492
Loan origination, year four	1,557	77
Loan origination, year five	0	0
Loan origination, more than five years	0	0
Revolving Loans	0	0
Total	11,490	11,729
Commercial Portfolio Segment \| Commercial and industrial \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loan origination, year one	0	0
Loan origination, year two	756	0
Loan origination, year three	0	39
Loan origination, year four	15	0
Loan origination, year five	0	0
Loan origination, more than five years	0	0
Revolving Loans	0	0
Total	771	39
Consumer and Other Portfolio Segment \| Consumer and other
Financing Receivable, Credit Quality Indicator [Line Items]
Loan origination, year one	55	25
Loan origination, year two	0	0
Loan origination, year three	0	0
Loan origination, year four	0	0
Loan origination, year five	0	0
Loan origination, more than five years	0	0
Revolving Loans	28	22
Total	83	47
Consumer and Other Portfolio Segment \| Consumer and other \| Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loan origination, year one	55	25
Loan origination, year two	0	0
Loan origination, year three	0	0
Loan origination, year four	0	0
Loan origination, year five	0	0
Loan origination, more than five years	0	0
Revolving Loans	28	22
Total	$ 83	$ 47

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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