LOANS RECEIVABLE, NET - Summary of loans receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 1,690,532	$ 1,583,482
Less: Allowance for credit losses on loans	14,392	12,965	$ 14,154
Loans receivable, net	1,676,140	1,570,517
Residential Portfolio Segment \| Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	510,583	518,243
Less: Allowance for credit losses on loans	2,194	1,989	1,968
Residential Portfolio Segment \| Multifamily
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	641,027	671,116
Less: Allowance for credit losses on loans	6,647	6,609	7,046
Commercial Real Estate Portfolio Segment \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	306,096	259,633
Less: Allowance for credit losses on loans	4,276	3,641	3,748
Construction and Land Portfolio Segment \| Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	51,353	85,546
Less: Allowance for credit losses on loans	900	460	1,222
Junior Lien Portfolio Segment \| Junior liens
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	31,008	25,422
Less: Allowance for credit losses on loans	159	109	76
Commercial Portfolio Segment \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	24,159	16,311
Less: Allowance for credit losses on loans	216	157	94
Consumer and Other Portfolio Segment \| Consumer and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	126,306	7,211
Less: Allowance for credit losses on loans	$ 0	$ 0	$ 0

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481628/310-20-40-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-2

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Section 45
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-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

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