ALLOWANCE FOR LOAN LOSSES: Schedule of reconciliation of the allowance for loan losses (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 9,885	$ 10,762	$ 12,551
Provision for (recapture of) loan losses		(1,150)	(1,800)
Charge-offs	(458)	(274)	(464)
Recoveries	1,101	547	475
Ending balance	10,528	9,885	10,762
Commercial and construction \| Commercial Business
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,048	1,263	2,409
Provision for (recapture of) loan losses	(121)	(245)	(1,060)
Charge-offs	(1)		(120)
Recoveries	492	30	34
Ending balance	1,418	1,048	1,263
Commercial and construction \| Commercial Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	4,273	4,268	5,269
Provision for (recapture of) loan losses	926	5	(768)
Charge-offs	(117)		(233)
Recoveries	2
Ending balance	5,084	4,273	4,268
Commercial and construction \| Land
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	325	539	340
Provision for (recapture of) loan losses	(558)	(545)	(72)
Charge-offs
Recoveries	461	331	271
Ending balance	228	325	539
Commercial and construction \| Multi-Family
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	712	348	203
Provision for (recapture of) loan losses	(415)	364	145
Charge-offs
Recoveries
Ending balance	297	712	348
Commercial and construction \| Real Estate Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	416	769	387
Provision for (recapture of) loan losses	298	(359)	382
Charge-offs
Recoveries		6
Ending balance	714	416	769
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,403	2,548	2,653
Provision for (recapture of) loan losses	(110)	(51)	(164)
Charge-offs	(340)	(274)	(111)
Recoveries	146	180	170
Ending balance	2,099	2,403	2,548
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	708	1,027	1,290
Provision for (recapture of) loan losses	(20)	(319)	(263)
Charge-offs
Recoveries
Ending balance	$ 688	$ 708	$ 1,027

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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No definition available.

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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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- 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
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 50
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

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