Loan Receivable and Allowance for Loan and Lease Losses Impaired loans (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Mar. 31, 2014
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Related Allowance	$ 1,357		$ 1,357		$ 1,631
Impaired Financing Receivable, Recorded Investment	17,258		17,258		22,502
Impaired Financing Receivable, Unpaid Principal Balance	18,092		18,092		23,328
Impaired Financing Receivable, Average Recorded Investment	17,341	25,360	16,159	28,304
Impaired Financing Receivable, Interest Income, Cash Basis Method	64	282	484	434
One- to four family loans [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	753		753		639
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	1,106		1,106		893
Impaired Financing Receivable, with Related Allowance, Recorded Investment	6,297		6,297		5,833
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	6,425		6,425		5,958
Impaired Financing Receivable, Related Allowance	899		899		520
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	736	1,793	731	1,889
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	2	4	11	5
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	6,299	5,210	6,106	5,464
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method	14	58	101	98
Multifamily Loans [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	156		156		0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	156		156		0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	1,334		1,334		2,240
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	1,432		1,432		2,240
Impaired Financing Receivable, Related Allowance	181		181		92
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	157	1,206	137	519
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	0	5	0	6
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	1,334	162	1,336	162
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method	2	0	17	0
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	2,937		2,937		3,972
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	3,109		3,109		4,147
Impaired Financing Receivable, with Related Allowance, Recorded Investment	1,168		1,168		4,812
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	1,168		1,168		5,023
Impaired Financing Receivable, Related Allowance	32		32		255
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	2,945	9,086	2,660	9,104
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	22	65	136	127
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	1,171	3,041	684	5,138
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method	(15)	32	24	37
Construction Loans [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	0	38	0	615
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	0	0	0	0
Business [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	952		952		341
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	952		952		402
Impaired Financing Receivable, with Related Allowance, Recorded Investment	3,654		3,654		4,664
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	3,737		3,737		4,664
Impaired Financing Receivable, Related Allowance	244		244		764
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	1,014	1,953	1,032	1,684
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	11	40	89	47
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	3,678	2,870	3,466	0
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method	28	78	106	0
Consumer Loan [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	0		0		1
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	0		0		1
Impaired Financing Receivable, with Related Allowance, Recorded Investment	7		7		0
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	7		7		0
Impaired Financing Receivable, Related Allowance	1		1		0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	0	1	0	1
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	0		0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	7	0	7	3,728
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method	$ 0		$ 0	$ 114

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5258-111524

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

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