Allowance for Loan Losses: Schedule of Analysis of Impaired Loans (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Mar. 31, 2012
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	$ 38,073	$ 45,535
Impaired Financing Receivable, with Related Allowance, Recorded Investment	5,332	20,178
Impaired Financing Receivable, Recorded Investment	43,405	65,713
Impaired Financing Receivable, Unpaid Principal Balance	50,698	83,690
Impaired Financing Receivable, Related Allowance	466	1,602
Impaired Financing Receivable, Average Recorded Investment, Quarterly	47,548
Impaired Financing Receivable, Average Recorded Investment, Year to date	53,603	53,379
Commercial business
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	3,117	4,790
Impaired Financing Receivable, with Related Allowance, Recorded Investment	290	3,028
Impaired Financing Receivable, Recorded Investment	3,407	7,818
Impaired Financing Receivable, Unpaid Principal Balance	3,561	10,477
Impaired Financing Receivable, Related Allowance	1	73
Impaired Financing Receivable, Average Recorded Investment, Quarterly	4,212
Impaired Financing Receivable, Average Recorded Investment, Year to date	5,414	6,400
Commercial Real Estate
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	16,653	12,704
Impaired Financing Receivable, with Related Allowance, Recorded Investment	2,227	10,120
Impaired Financing Receivable, Recorded Investment	18,880	22,824
Impaired Financing Receivable, Unpaid Principal Balance	20,068	25,359
Impaired Financing Receivable, Related Allowance	295	686
Impaired Financing Receivable, Average Recorded Investment, Quarterly	21,022
Impaired Financing Receivable, Average Recorded Investment, Year to date	21,623	17,102
Land
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	4,391	10,365
Impaired Financing Receivable, with Related Allowance, Recorded Investment	1,158	3,861
Impaired Financing Receivable, Recorded Investment	5,549	14,226
Impaired Financing Receivable, Unpaid Principal Balance	6,163	17,989
Impaired Financing Receivable, Related Allowance	17	624
Impaired Financing Receivable, Average Recorded Investment, Quarterly	5,804
Impaired Financing Receivable, Average Recorded Investment, Year to date	8,611	13,339
Multi-Family
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	8,836	7,825
Impaired Financing Receivable, with Related Allowance, Recorded Investment	437	440
Impaired Financing Receivable, Recorded Investment	9,273	8,265
Impaired Financing Receivable, Unpaid Principal Balance	10,231	9,189
Impaired Financing Receivable, Related Allowance	24	4
Impaired Financing Receivable, Average Recorded Investment, Quarterly	9,855
Impaired Financing Receivable, Average Recorded Investment, Year to date	9,325	8,254
Real estate construction
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	1,476	7,009
Impaired Financing Receivable, with Related Allowance, Recorded Investment		604
Impaired Financing Receivable, Recorded Investment	1,476	7,613
Impaired Financing Receivable, Unpaid Principal Balance	4,918	13,796
Impaired Financing Receivable, Related Allowance		18
Impaired Financing Receivable, Average Recorded Investment, Quarterly	1,674
Impaired Financing Receivable, Average Recorded Investment, Year to date	3,653	6,700
Total consumer
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	3,600	2,842
Impaired Financing Receivable, with Related Allowance, Recorded Investment	1,220	2,125
Impaired Financing Receivable, Recorded Investment	4,820	4,967
Impaired Financing Receivable, Unpaid Principal Balance	5,757	6,880
Impaired Financing Receivable, Related Allowance	129	197
Impaired Financing Receivable, Average Recorded Investment, Quarterly	4,981
Impaired Financing Receivable, Average Recorded Investment, Year to date	$ 4,977	$ 1,584