FAIR VALUE OF ASSETS AND LIABILITIES - Summary of assets and liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Financial assets
Securities available-for-sale:	$ 309,083	$ 314,248
U.S. Treasury Note
Financial assets
Securities available-for-sale:	44,295	43,759
Corporate bonds
Financial assets
Securities available-for-sale:	76,522	76,298
U.S. Government agency obligations
Financial assets
Securities available-for-sale:	14,911	15,423
Obligations issued by U.S. states and their political subdivisions
Financial assets
Securities available-for-sale:	16,379	16,268
Residential one-to-four family
Financial assets
Securities available-for-sale:	139,318	140,186
Multifamily
Financial assets
Securities available-for-sale:	13,462	18,158
Asset-backed securities
Financial assets
Securities available-for-sale:	4,196	4,156
Measured on a recurring basis:
Financial assets
Securities available-for-sale:	309,083	314,248
Derivatives	9,612	11,091
Financial assets	318,695	325,339
Financial Liabilities
Derivatives	965	0
Measured on a recurring basis: \| U.S. Treasury Note
Financial assets
Securities available-for-sale:	44,295	43,759
Measured on a recurring basis: \| Corporate bonds
Financial assets
Securities available-for-sale:	76,522	76,298
Measured on a recurring basis: \| U.S. Government agency obligations
Financial assets
Securities available-for-sale:	14,911	15,423
Measured on a recurring basis: \| Obligations issued by U.S. states and their political subdivisions
Financial assets
Securities available-for-sale:	16,379	16,268
Measured on a recurring basis: \| Residential one-to-four family
Financial assets
Securities available-for-sale:	139,318	140,186
Measured on a recurring basis: \| Multifamily
Financial assets
Securities available-for-sale:	13,462	18,158
Measured on a recurring basis: \| Asset-backed securities
Financial assets
Securities available-for-sale:	4,196	4,156
Measured on a recurring basis: \| Quoted Prices in Active Markets for Identical Assets
Financial assets
Securities available-for-sale:	54,522	55,054
Derivatives	0	0
Financial assets	54,522	55,054
Financial Liabilities
Derivatives	0	0
Measured on a recurring basis: \| Quoted Prices in Active Markets for Identical Assets \| U.S. Treasury Note
Financial assets
Securities available-for-sale:	44,295	43,759
Measured on a recurring basis: \| Quoted Prices in Active Markets for Identical Assets \| Corporate bonds
Financial assets
Securities available-for-sale:	0	0
Measured on a recurring basis: \| Quoted Prices in Active Markets for Identical Assets \| U.S. Government agency obligations
Financial assets
Securities available-for-sale:	10,227	11,295
Measured on a recurring basis: \| Quoted Prices in Active Markets for Identical Assets \| Obligations issued by U.S. states and their political subdivisions
Financial assets
Securities available-for-sale:	0	0
Measured on a recurring basis: \| Quoted Prices in Active Markets for Identical Assets \| Residential one-to-four family
Financial assets
Securities available-for-sale:	0	0
Measured on a recurring basis: \| Quoted Prices in Active Markets for Identical Assets \| Multifamily
Financial assets
Securities available-for-sale:	0	0
Measured on a recurring basis: \| Quoted Prices in Active Markets for Identical Assets \| Asset-backed securities
Financial assets
Securities available-for-sale:	0	0
Measured on a recurring basis: \| Significant Other Observable Inputs
Financial assets
Securities available-for-sale:	254,561	259,194
Derivatives	9,612	11,091
Financial assets	264,173	270,285
Financial Liabilities
Derivatives	965	0
Measured on a recurring basis: \| Significant Other Observable Inputs \| U.S. Treasury Note
Financial assets
Securities available-for-sale:	0	0
Measured on a recurring basis: \| Significant Other Observable Inputs \| Corporate bonds
Financial assets
Securities available-for-sale:	76,522	76,298
Measured on a recurring basis: \| Significant Other Observable Inputs \| U.S. Government agency obligations
Financial assets
Securities available-for-sale:	4,684	4,128
Measured on a recurring basis: \| Significant Other Observable Inputs \| Obligations issued by U.S. states and their political subdivisions
Financial assets
Securities available-for-sale:	16,379	16,268
Measured on a recurring basis: \| Significant Other Observable Inputs \| Residential one-to-four family
Financial assets
Securities available-for-sale:	139,318	140,186
Measured on a recurring basis: \| Significant Other Observable Inputs \| Multifamily
Financial assets
Securities available-for-sale:	13,462	18,158
Measured on a recurring basis: \| Significant Other Observable Inputs \| Asset-backed securities
Financial assets
Securities available-for-sale:	4,196	4,156
Measured on a recurring basis: \| Significant Unobservable Inputs
Financial assets
Securities available-for-sale:	0	0
Derivatives	0	0
Financial assets	0	0
Financial Liabilities
Derivatives	0	0
Measured on a recurring basis: \| Significant Unobservable Inputs \| U.S. Treasury Note
Financial assets
Securities available-for-sale:	0	0
Measured on a recurring basis: \| Significant Unobservable Inputs \| Corporate bonds
Financial assets
Securities available-for-sale:	0	0
Measured on a recurring basis: \| Significant Unobservable Inputs \| U.S. Government agency obligations
Financial assets
Securities available-for-sale:	0	0
Measured on a recurring basis: \| Significant Unobservable Inputs \| Obligations issued by U.S. states and their political subdivisions
Financial assets
Securities available-for-sale:	0	0
Measured on a recurring basis: \| Significant Unobservable Inputs \| Residential one-to-four family
Financial assets
Securities available-for-sale:	0	0
Measured on a recurring basis: \| Significant Unobservable Inputs \| Multifamily
Financial assets
Securities available-for-sale:	0	0
Measured on a recurring basis: \| Significant Unobservable Inputs \| Asset-backed securities
Financial assets
Securities available-for-sale:	$ 0	0
Measured on a nonrecurring basis: \| Assets held for sale
Financial assets
Derivatives		917
Measured on a nonrecurring basis: \| Quoted Prices in Active Markets for Identical Assets \| Assets held for sale
Financial assets
Derivatives		0
Measured on a nonrecurring basis: \| Significant Other Observable Inputs \| Assets held for sale
Financial assets
Derivatives		917
Measured on a nonrecurring basis: \| Significant Unobservable Inputs \| Assets held for sale
Financial assets
Derivatives		$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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