ALLOWANCE FOR LOAN LOSSES: Reconciliation of the allowance for loan losses (Details) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 10,766	$ 10,528
Provision for (recapture of) loan losses	(200)	0
Charge-offs	(92)	(82)
Recoveries	875	151
Ending balance	11,349	10,597
Commercial and construction \| Commercial Business
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,668	1,418
Provision for (recapture of) loan losses	131	(30)
Charge-offs	0	0
Recoveries	0	3
Ending balance	1,799	1,391
Commercial and construction \| Commercial Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	4,914	5,084
Provision for (recapture of) loan losses	(598)	92
Charge-offs	0	0
Recoveries	823	0
Ending balance	5,139	5,176
Commercial and construction \| Land
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	220	228
Provision for (recapture of) loan losses	38	(146)
Charge-offs	0	0
Recoveries	0	137
Ending balance	258	219
Commercial and construction \| Multi-Family
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	822	297
Provision for (recapture of) loan losses	(41)	205
Charge-offs	0	0
Recoveries	0	0
Ending balance	781	502
Commercial and construction \| Real Estate Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	618	714
Provision for (recapture of) loan losses	237	(46)
Charge-offs	0	0
Recoveries	0	0
Ending balance	855	668
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,809	2,099
Provision for (recapture of) loan losses	19	(96)
Charge-offs	(92)	(82)
Recoveries	52	11
Ending balance	1,788	1,932
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	715	688
Provision for (recapture of) loan losses	14	21
Charge-offs	0	0
Recoveries	0	0
Ending balance	$ 729	$ 709

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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