ALLOWANCE FOR LOAN LOSSES: Credit Quality Indicators (Details 4) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	$ 811,376	$ 779,432
Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	792,298	756,388
Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	11,655	13,036
Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	7,423	10,008
Doubtful
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	0	0
Loss
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	0	0
Commercial and construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	706,270	660,189
Commercial and construction | Commercial business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	137,672	107,371
Commercial and construction | Commercial business | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	132,309	102,113
Commercial and construction | Commercial business | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	1,976	2,063
Commercial and construction | Commercial business | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	3,387	3,195
Commercial and construction | Commercial business | Doubtful
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	0	0
Commercial and construction | Commercial business | Loss
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	0	0
Commercial and construction | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	450,597	447,071
Commercial and construction | Commercial real estate | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	440,123	430,923
Commercial and construction | Commercial real estate | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	7,489	10,426
Commercial and construction | Commercial real estate | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	2,985	5,722
Commercial and construction | Commercial real estate | Doubtful
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	0	0
Commercial and construction | Commercial real estate | Loss
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	0	0
Commercial and construction | Land
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	15,337	15,875
Commercial and construction | Land | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	14,574	15,074
Commercial and construction | Land | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	0	0
Commercial and construction | Land | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	763	801
Commercial and construction | Land | Doubtful
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	0	0
Commercial and construction | Land | Loss
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	0	0
Commercial and construction | Multi-family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	63,080	43,715
Commercial and construction | Multi-family | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	60,879	43,156
Commercial and construction | Multi-family | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	2,190	547
Commercial and construction | Multi-family | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	11	12
Commercial and construction | Multi-family | Doubtful
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	0	0
Commercial and construction | Multi-family | Loss
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	0	0
Commercial and construction | Real estate construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	39,584	46,157
Commercial and construction | Real estate construction | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	39,584	46,157
Commercial and construction | Real estate construction | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	0	0
Commercial and construction | Real estate construction | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	0	0
Commercial and construction | Real estate construction | Doubtful
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	0	0
Commercial and construction | Real estate construction | Loss
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	0	0
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	105,106	119,243
Consumer | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	104,829	118,965
Consumer | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	0	0
Consumer | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	277	278
Consumer | Doubtful
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	0	0
Consumer | Loss
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans Receivable	$ 0	$ 0