LOANS RECEIVABLE, NET - Schedule of loan modifications (Details)	12 Months Ended
Dec. 31, 2023 USD ($)
Financing Receivable, Modified [Line Items]
Loans modified in period	$ 8,925,000
Loans modified in period, percentage of total loans	0.57%
Loans modified in period with subsequent default	$ 0
Current
Financing Receivable, Modified [Line Items]
Loans modified in period	7,520,000
60-89 Days Past Due
Financing Receivable, Modified [Line Items]
Loans modified in period	0
30-59 Days Past Due
Financing Receivable, Modified [Line Items]
Loans modified in period	0
90 Days and Greater Past Due
Financing Receivable, Modified [Line Items]
Loans modified in period	0
Nonaccrual
Financing Receivable, Modified [Line Items]
Loans modified in period	1,405,000
Payment Deferral
Financing Receivable, Modified [Line Items]
Loans modified in period	2,431,000
Extended Maturity
Financing Receivable, Modified [Line Items]
Loans modified in period	6,494,000
Construction
Financing Receivable, Modified [Line Items]
Loans modified in period	$ 3,525,000
Loans modified in period, percentage of total loans	5.83%
Residential Portfolio Segment \| Residential one-to-four family
Financing Receivable, Modified [Line Items]
Loans modified in period	$ 2,805,000
Loans modified in period, percentage of total loans	0.51%
Term extension duration	240 months
Residential Portfolio Segment \| Residential one-to-four family \| Current
Financing Receivable, Modified [Line Items]
Loans modified in period	$ 1,400,000
Residential Portfolio Segment \| Residential one-to-four family \| 60-89 Days Past Due
Financing Receivable, Modified [Line Items]
Loans modified in period	0
Residential Portfolio Segment \| Residential one-to-four family \| 30-59 Days Past Due
Financing Receivable, Modified [Line Items]
Loans modified in period	0
Residential Portfolio Segment \| Residential one-to-four family \| 90 Days and Greater Past Due
Financing Receivable, Modified [Line Items]
Loans modified in period	0
Residential Portfolio Segment \| Residential one-to-four family \| Nonaccrual
Financing Receivable, Modified [Line Items]
Loans modified in period	1,405,000
Residential Portfolio Segment \| Residential one-to-four family \| Payment Deferral
Financing Receivable, Modified [Line Items]
Loans modified in period	2,431,000
Residential Portfolio Segment \| Residential one-to-four family \| Extended Maturity
Financing Receivable, Modified [Line Items]
Loans modified in period	374,000
Residential Portfolio Segment \| Multifamily
Financing Receivable, Modified [Line Items]
Loans modified in period	$ 2,595,000
Loans modified in period, percentage of total loans	0.38%
Residential Portfolio Segment \| Multifamily \| Minimum
Financing Receivable, Modified [Line Items]
Term extension duration	90 days
Residential Portfolio Segment \| Multifamily \| Maximum
Financing Receivable, Modified [Line Items]
Term extension duration	180 days
Residential Portfolio Segment \| Multifamily \| Current
Financing Receivable, Modified [Line Items]
Loans modified in period	$ 2,595,000
Residential Portfolio Segment \| Multifamily \| 60-89 Days Past Due
Financing Receivable, Modified [Line Items]
Loans modified in period	0
Residential Portfolio Segment \| Multifamily \| 30-59 Days Past Due
Financing Receivable, Modified [Line Items]
Loans modified in period	0
Residential Portfolio Segment \| Multifamily \| 90 Days and Greater Past Due
Financing Receivable, Modified [Line Items]
Loans modified in period	0
Residential Portfolio Segment \| Multifamily \| Nonaccrual
Financing Receivable, Modified [Line Items]
Loans modified in period	0
Residential Portfolio Segment \| Multifamily \| Payment Deferral
Financing Receivable, Modified [Line Items]
Loans modified in period	0
Residential Portfolio Segment \| Multifamily \| Extended Maturity
Financing Receivable, Modified [Line Items]
Loans modified in period	2,595,000
Construction \| Construction
Financing Receivable, Modified [Line Items]
Loans modified in period	$ 3,525,000
Term extension duration	180 days
Construction \| Construction \| Current
Financing Receivable, Modified [Line Items]
Loans modified in period	$ 3,525,000
Construction \| Construction \| 60-89 Days Past Due
Financing Receivable, Modified [Line Items]
Loans modified in period	0
Construction \| Construction \| 30-59 Days Past Due
Financing Receivable, Modified [Line Items]
Loans modified in period	0
Construction \| Construction \| 90 Days and Greater Past Due
Financing Receivable, Modified [Line Items]
Loans modified in period	0
Construction \| Construction \| Nonaccrual
Financing Receivable, Modified [Line Items]
Loans modified in period	0
Construction \| Construction \| Payment Deferral
Financing Receivable, Modified [Line Items]
Loans modified in period	0
Construction \| Construction \| Extended Maturity
Financing Receivable, Modified [Line Items]
Loans modified in period	$ 3,525,000

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