ALLOWANCE FOR LOAN LOSSES - Reconciliation of the allowance for loan losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 11,442	$ 11,349	$ 11,457	$ 10,766
Provision for (recapture of) loan losses	0	250	0	50
Charge-offs	(13)	(92)	(57)	(184)
Recoveries	7	6	36	881
Ending balance	11,436	11,513	11,436	11,513
Commercial Business
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance	150		150
Commercial Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance	1,000		1,000
Commercial Real Estate Portfolio Segment \| Commercial Business
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,113	1,799	1,808	1,668
Provision for (recapture of) loan losses	(62)	59	246	190
Charge-offs	0	0	(3)	0
Recoveries	0	0	0	0
Ending balance	2,051	1,858	2,051	1,858
Commercial Real Estate Portfolio Segment \| Commercial Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	4,889	5,139	5,053	4,914
Provision for (recapture of) loan losses	149	222	(15)	(376)
Charge-offs	0	0	0	0
Recoveries	0	0	0	823
Ending balance	5,038	5,361	5,038	5,361
Commercial Real Estate Portfolio Segment \| Land
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	244	258	254	220
Provision for (recapture of) loan losses	(25)	(21)	(35)	17
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	219	237	219	237
Commercial Real Estate Portfolio Segment \| Multi-Family
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	699	781	728	822
Provision for (recapture of) loan losses	80	(85)	51	(126)
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	779	696	779	696
Commercial Real Estate Portfolio Segment \| Real Estate Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,506	855	1,457	618
Provision for (recapture of) loan losses	(125)	152	(76)	389
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	1,381	1,007	1,381	1,007
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,346	1,788	1,447	1,809
Provision for (recapture of) loan losses	7	(61)	(82)	(42)
Charge-offs	(13)	(92)	(54)	(184)
Recoveries	7	6	36	58
Ending balance	1,347	1,641	1,347	1,641
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	645	729	710	715
Provision for (recapture of) loan losses	(24)	(16)	(89)	(2)
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	$ 621	$ 713	$ 621	$ 713

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

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- Definition

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

+ References

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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

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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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