Loan Receivable and Allowance for Loan and Lease Losses Non-performing loans (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Mar. 31, 2015
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Held-for-sale, Fair Value Disclosure	$ 2,586	$ 2,576
Other Real Estate, Foreclosed Assets, and Repossessed Assets	3,723	4,341
Financing Receivable, Recorded Investment, Nonaccrual Status	6,484	8,395
Impaired and non performing TDR loans	1,000	3,600
Consumer Loan [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	0	0
One- to four family loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	3,251	3,664
Multifamily Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	1,241	1,053
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	0	2,817
Construction Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	0	0
Business [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	$ 1,992	$ 861