ALLOWANCE FOR LOAN LOSSES: Schedule of reconciliation of the allowance for loan losses (Details) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2017	Jun. 30, 2016
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 10,528	$ 9,885
Provision for (recapture of) loan losses
Charge-offs	(82)	(44)
Recoveries	151	119
Ending balance	10,597	9,960
Commercial Business
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,418	1,048
Provision for (recapture of) loan losses	(30)	(150)
Charge-offs
Recoveries	3	4
Ending balance	1,391	902
Commercial Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	5,084	4,273
Provision for (recapture of) loan losses	92	198
Charge-offs
Recoveries		2
Ending balance	5,176	4,473
Land
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	228	325
Provision for (recapture of) loan losses	(146)	(95)
Charge-offs
Recoveries	137	82
Ending balance	219	312
Multi-Family
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	297	712
Provision for (recapture of) loan losses	205	(41)
Charge-offs
Recoveries
Ending balance	502	671
Real Estate Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	714	416
Provision for (recapture of) loan losses	(46)	149
Charge-offs
Recoveries
Ending balance	668	565
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,099	2,403
Provision for (recapture of) loan losses	(96)	(63)
Charge-offs	(82)	(44)
Recoveries	11	31
Ending balance	1,932	2,327
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	688	708
Provision for (recapture of) loan losses	21	2
Charge-offs
Recoveries
Ending balance	$ 709	$ 710

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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- 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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-Publisher FASB
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Amount of expense related to estimated loss from loan and lease transactions.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 225
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