ALLOWANCE FOR LOAN LOSSES: Schedule of reconciliation of the allowance for loan losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 10,597	$ 9,960	$ 10,528	$ 9,885
Charge-offs	(128)	(71)	(210)	(115)
Recoveries	148	174	299	293
Ending balance	10,617	10,063	10,617	10,063
Commercial Business
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,391	902	1,418	1,048
Provision for (recapture of) loan losses	(53)	1	(83)	(149)
Recoveries	2	6	5	10
Ending balance	1,340	909	1,340	909
Commercial Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	5,176	4,473	5,084	4,273
Provision for (recapture of) loan losses	(76)	216	16	414
Recoveries	16		16	2
Ending balance	5,116	4,689	5,116	4,689
Land
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	219	312	228	325
Provision for (recapture of) loan losses	(130)	(264)	(275)	(359)
Recoveries	107	106	243	188
Ending balance	196	154	196	154
Multi-Family
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	502	671	297	712
Provision for (recapture of) loan losses	2	(58)	207	(99)
Ending balance	504	613	504	613
Real Estate Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	668	565	714	416
Provision for (recapture of) loan losses	172	162	126	311
Ending balance	840	727	840	727
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,932	2,327	2,099	2,403
Provision for (recapture of) loan losses	63	(28)	(34)	(91)
Charge-offs	(128)	(71)	(210)	(115)
Recoveries	23	62	35	93
Ending balance	1,890	2,290	1,890	2,290
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	709	710	688	708
Provision for (recapture of) loan losses	22	(29)	43	(27)
Ending balance	$ 731	$ 681	$ 731	$ 681

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.

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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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- Definition

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
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 225
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