LOANS AND ALLOWANCE FOR CREDIT LOSSES - Reconciliation of the allowance for loan losses (Details) - USD ($)	3 Months Ended			6 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Reconciliation of the allowance for loan losses
Beginning balance	$ 15,343,000	$ 15,309,000		$ 15,309,000
Charge-offs				(11,000)
Recoveries	3,000			6,000
Ending balance	15,346,000	15,343,000		15,346,000
Reconciliation of the allowance for loan losses
Beginning balance		15,309,000	$ 14,559,000	15,309,000	$ 14,523,000
Charge-offs			(10,000)		(16,000)
Recoveries			3,000		45,000
Ending balance			14,552,000		14,552,000
Adjustment | ASU 2016-13
Reconciliation of the allowance for loan losses
Beginning balance		42,000		42,000
Commercial Real Estate Portfolio Segment | Commercial Business
Reconciliation of the allowance for loan losses
Beginning balance	5,215,000	3,123,000		3,123,000
Provision for (recapture of) credit losses	124,000			332,000
Ending balance	5,339,000	5,215,000		5,339,000
Reconciliation of the allowance for loan losses
Beginning balance		3,123,000	2,495,000	3,123,000	2,422,000
Provision for (recapture of) loan losses			294,000		367,000
Ending balance			2,789,000		2,789,000
Commercial Real Estate Portfolio Segment | Commercial Business | Adjustment | ASU 2016-13
Reconciliation of the allowance for loan losses
Beginning balance		1,884,000		1,884,000
Commercial Real Estate Portfolio Segment | Commercial Real Estate
Reconciliation of the allowance for loan losses
Beginning balance	7,205,000	8,894,000		8,894,000
Provision for (recapture of) credit losses	(67,000)			(262,000)
Ending balance	7,138,000	7,205,000		7,138,000
Reconciliation of the allowance for loan losses
Beginning balance		8,894,000	8,542,000	8,894,000	9,037,000
Provision for (recapture of) loan losses			(312,000)		(807,000)
Ending balance			8,230,000		8,230,000
Commercial Real Estate Portfolio Segment | Commercial Real Estate | Adjustment | ASU 2016-13
Reconciliation of the allowance for loan losses
Beginning balance		(1,494,000)		(1,494,000)
Commercial Real Estate Portfolio Segment | Land
Reconciliation of the allowance for loan losses
Beginning balance	123,000	93,000		93,000
Provision for (recapture of) credit losses	(11,000)			(21,000)
Ending balance	112,000	123,000		112,000
Reconciliation of the allowance for loan losses
Beginning balance		93,000	149,000	93,000	168,000
Provision for (recapture of) loan losses			(25,000)		(44,000)
Ending balance			124,000		124,000
Commercial Real Estate Portfolio Segment | Land | Adjustment | ASU 2016-13
Reconciliation of the allowance for loan losses
Beginning balance		40,000		40,000
Commercial Real Estate Portfolio Segment | Multi-Family
Reconciliation of the allowance for loan losses
Beginning balance	293,000	798,000		798,000
Provision for (recapture of) credit losses				(13,000)
Ending balance	293,000	293,000		293,000
Reconciliation of the allowance for loan losses
Beginning balance		798,000	862,000	798,000	845,000
Provision for (recapture of) loan losses			(6,000)		11,000
Ending balance			856,000		856,000
Commercial Real Estate Portfolio Segment | Multi-Family | Adjustment | ASU 2016-13
Reconciliation of the allowance for loan losses
Beginning balance		(492,000)		(492,000)
Commercial Real Estate Portfolio Segment | Real Estate Construction
Reconciliation of the allowance for loan losses
Beginning balance	830,000	764,000		764,000
Provision for (recapture of) credit losses	30,000			(35,000)
Ending balance	860,000	830,000		860,000
Reconciliation of the allowance for loan losses
Beginning balance		764,000	518,000	764,000	393,000
Provision for (recapture of) loan losses			120,000		245,000
Ending balance			638,000		638,000
Commercial Real Estate Portfolio Segment | Real Estate Construction | Adjustment | ASU 2016-13
Reconciliation of the allowance for loan losses
Beginning balance		131,000		131,000
Consumer
Reconciliation of the allowance for loan losses
Beginning balance	1,677,000	1,127,000		1,127,000
Provision for (recapture of) credit losses	(76,000)			(1,000)
Charge-offs				(11,000)
Recoveries	3,000			6,000
Ending balance	$ 1,604,000	1,677,000		1,604,000
Reconciliation of the allowance for loan losses
Beginning balance		1,127,000	1,236,000	1,127,000	943,000
Provision for (recapture of) loan losses			(4,000)		253,000
Charge-offs			(10,000)		(16,000)
Recoveries			3,000		45,000
Ending balance			1,225,000		1,225,000
Consumer | ASU 2016-13
Reconciliation of the allowance for loan losses
Recoveries		0
Consumer | Adjustment | ASU 2016-13
Reconciliation of the allowance for loan losses
Beginning balance		483,000		483,000
Unallocated
Reconciliation of the allowance for loan losses
Beginning balance		510,000		510,000
Reconciliation of the allowance for loan losses
Beginning balance		510,000	757,000	510,000	715,000
Provision for (recapture of) loan losses			(67,000)		(25,000)
Ending balance			$ 690,000		$ 690,000
Unallocated | Adjustment | ASU 2016-13
Reconciliation of the allowance for loan losses
Beginning balance		$ (510,000)		$ (510,000)