ALLOWANCE FOR LOAN LOSSES: Reconciliation of the allowance for loan losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 11,513	$ 10,617	$ 10,766	$ 10,528
Provision for (recapture of) loan losses	0	0	50	0
Charge-offs	(52)	(46)	(236)	(257)
Recoveries	41	296	922	596
Ending balance	11,502	10,867	11,502	10,867
Commercial and construction \| Commercial Business
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,858	1,340	1,668	1,418
Provision for (recapture of) loan losses	84	(186)	274	(270)
Charge-offs	0	0	0	0
Recoveries	0	220	0	226
Ending balance	1,942	1,374	1,942	1,374
Commercial and construction \| Commercial Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	5,361	5,116	4,914	5,084
Provision for (recapture of) loan losses	(80)	(26)	(456)	40
Charge-offs	0	0	0	0
Recoveries	0	65	823	31
Ending balance	5,281	5,155	5,281	5,155
Commercial and construction \| Land
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	237	196	220	228
Provision for (recapture of) loan losses	31	(19)	48	(344)
Charge-offs	0	0	0	0
Recoveries	0	0	0	293
Ending balance	268	177	268	177
Commercial and construction \| Multi-Family
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	696	504	822	297
Provision for (recapture of) loan losses	19	295	(107)	502
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	715	799	715	799
Commercial and construction \| Real Estate Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,007	840	618	714
Provision for (recapture of) loan losses	186	(206)	575	(80)
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	1,193	634	1,193	634
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,641	1,890	1,809	2,099
Provision for (recapture of) loan losses	(177)	81	(219)	48
Charge-offs	(52)	(46)	(236)	(257)
Recoveries	41	11	99	46
Ending balance	1,453	1,936	1,453	1,936
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	713	731	715	688
Provision for (recapture of) loan losses	(63)	61	(65)	104
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	$ 650	$ 792	$ 650	$ 792

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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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.

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

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