ALLOWANCE FOR LOAN LOSSES: Reconciliation of the allowance for loan losses (Details) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 11,457	$ 10,766
Provision for (recapture of) loan losses	0	(200)
Charge-offs	(44)	(92)
Recoveries	29	875
Ending balance	11,442	11,349
Commercial and construction \| Commercial Business
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,808	1,668
Provision for (recapture of) loan losses	308	131
Charge-offs	(3)	0
Recoveries	0	0
Ending balance	2,113	1,799
Commercial and construction \| Commercial Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	5,053	4,914
Provision for (recapture of) loan losses	164	(598)
Charge-offs	0	0
Recoveries	0	823
Ending balance	4,889	5,139
Commercial and construction \| Land
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	254	220
Provision for (recapture of) loan losses	(10)	38
Charge-offs	0	0
Recoveries	0	0
Ending balance	244	258
Commercial and construction \| Multi-Family
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	728	822
Provision for (recapture of) loan losses	(29)	(41)
Charge-offs	0	0
Recoveries	0	0
Ending balance	699	781
Commercial and construction \| Real Estate Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,457	618
Provision for (recapture of) loan losses	49	237
Charge-offs	0	0
Recoveries	0	0
Ending balance	1,506	855
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,447	1,809
Provision for (recapture of) loan losses	(89)	19
Charge-offs	(41)	(92)
Recoveries	29	52
Ending balance	1,346	1,788
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	710	715
Provision for (recapture of) loan losses	(65)	14
Charge-offs	0	0
Recoveries	0	0
Ending balance	$ 645	$ 729

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

No definition available.

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- Definition

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
-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.

+ References

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- Definition

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

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