ALLOWANCE FOR LOAN LOSSES - Reconciliation of the allowance for loan losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Reconciliation of the allowance for loan losses
Beginning balance	$ 17,590	$ 17,076	$ 19,178	$ 12,624
Provision for (recapture of) loan losses	(1,100)	1,800	(2,700)	6,300
Charge-offs	(4)	(23)	(13)	(88)
Recoveries	14	13	35	30
Ending balance	16,500	18,866	16,500	18,866
Commercial Real Estate Portfolio Segment \| Commercial Business
Reconciliation of the allowance for loan losses
Beginning balance	2,202	2,011	2,416	2,008
Provision for (recapture of) loan losses	59	169	(155)	162
Recoveries				10
Ending balance	2,261	2,180	2,261	2,180
Commercial Real Estate Portfolio Segment \| Commercial Real Estate
Reconciliation of the allowance for loan losses
Beginning balance	12,942	11,323	14,089	6,421
Provision for (recapture of) loan losses	(1,147)	1,886	(2,294)	6,788
Ending balance	11,795	13,209	11,795	13,209
Commercial Real Estate Portfolio Segment \| Land
Reconciliation of the allowance for loan losses
Beginning balance	237	243	233	230
Provision for (recapture of) loan losses	(5)	2	(1)	15
Ending balance	232	245	232	245
Commercial Real Estate Portfolio Segment \| Multi-Family
Reconciliation of the allowance for loan losses
Beginning balance	607	879	638	854
Provision for (recapture of) loan losses	(77)	(134)	(108)	(109)
Ending balance	530	745	530	745
Commercial Real Estate Portfolio Segment \| Real Estate Construction
Reconciliation of the allowance for loan losses
Beginning balance	197	692	294	1,149
Provision for (recapture of) loan losses	34	28	(63)	(429)
Ending balance	231	720	231	720
Consumer
Reconciliation of the allowance for loan losses
Beginning balance	712	1,281	852	1,363
Provision for (recapture of) loan losses	119	(116)	(33)	(140)
Charge-offs	(4)	(23)	(13)	(88)
Recoveries	14	13	35	20
Ending balance	841	1,155	841	1,155
Unallocated
Reconciliation of the allowance for loan losses
Beginning balance	693	647	656	599
Provision for (recapture of) loan losses	(83)	(35)	(46)	13
Ending balance	$ 610	$ 612	$ 610	$ 612

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(4)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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Amount of expense related to estimated loss from loan and lease transactions.

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