ALLOWANCE FOR LOAN LOSSES - Reconciliation of the allowance for loan losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Reconciliation of the allowance for loan losses
Beginning balance	$ 18,866	$ 11,436	$ 12,624	$ 11,457
Provision for (recapture of) loan losses	0	0	6,300	0
Charge-offs	(15)	(13)	(103)	(70)
Recoveries	341	10	371	46
Ending balance	19,192	11,433	19,192	11,433
Commercial Real Estate Portfolio Segment \| Commercial Business
Reconciliation of the allowance for loan losses
Beginning balance	2,180	2,051	2,008	1,808
Provision for (recapture of) loan losses	286	0	448	246
Charge-offs	0	0	0	(3)
Recoveries	0	0	10	0
Ending balance	2,466	2,051	2,466	2,051
Commercial Real Estate Portfolio Segment \| Commercial Real Estate
Reconciliation of the allowance for loan losses
Beginning balance	13,209	5,038	6,421	5,053
Provision for (recapture of) loan losses	181	(20)	6,969	(35)
Charge-offs	0	0	0	0
Recoveries	332	0	332	0
Ending balance	13,722	5,018	13,722	5,018
Commercial Real Estate Portfolio Segment \| Land
Reconciliation of the allowance for loan losses
Beginning balance	245	219	230	254
Provision for (recapture of) loan losses	(43)	16	(28)	(19)
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	202	235	202	235
Commercial Real Estate Portfolio Segment \| Multi-Family
Reconciliation of the allowance for loan losses
Beginning balance	745	779	854	728
Provision for (recapture of) loan losses	(121)	(14)	(230)	37
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	624	765	624	765
Commercial Real Estate Portfolio Segment \| Real Estate Construction
Reconciliation of the allowance for loan losses
Beginning balance	720	1,381	1,149	1,457
Provision for (recapture of) loan losses	(198)	86	(627)	10
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	522	1,467	522	1,467
Consumer
Reconciliation of the allowance for loan losses
Beginning balance	1,155	1,347	1,363	1,447
Provision for (recapture of) loan losses	(137)	(76)	(277)	(158)
Charge-offs	(15)	(13)	(103)	(67)
Recoveries	9	10	29	46
Ending balance	1,012	1,268	1,012	1,268
Unallocated
Reconciliation of the allowance for loan losses
Beginning balance	612	621	599	710
Provision for (recapture of) loan losses	32	8	45	(81)
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	$ 644	$ 629	$ 644	$ 629

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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