Past due financing receivable (Details) - USD ($) $ in Thousands	Mar. 31, 2015	Mar. 31, 2014
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, 30 to 59 Days Past Due	$ 1,614	$ 3,823
Financing Receivable, Recorded Investment, 60 to 89 Days Past Due	1,371	1,313
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	5,853	8,988
Financing Receivable, Recorded Investment, Past Due	8,838	14,124
Financing Receivable, Recorded Investment, Current	474,355	375,832
Loans Receivable, Net	483,193	389,956
One- to four family loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, 30 to 59 Days Past Due	464	244
Financing Receivable, Recorded Investment, 60 to 89 Days Past Due	0	888
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	3,574	1,863
Financing Receivable, Recorded Investment, Past Due	4,038	2,995
Financing Receivable, Recorded Investment, Current	122,489	109,196
Loans Receivable, Net	126,527	112,191
Multifamily Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, 30 to 59 Days Past Due	0	444
Financing Receivable, Recorded Investment, 60 to 89 Days Past Due	434	0
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	1,054	2,240
Financing Receivable, Recorded Investment, Past Due	1,488	2,684
Financing Receivable, Recorded Investment, Current	93,218	44,841
Loans Receivable, Net	94,706	47,525
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, 30 to 59 Days Past Due	1,150	3,133
Financing Receivable, Recorded Investment, 60 to 89 Days Past Due	936	292
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	1,102	3,891
Financing Receivable, Recorded Investment, Past Due	3,188	7,316
Financing Receivable, Recorded Investment, Current	182,663	190,785
Loans Receivable, Net	185,851	198,101
Construction Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, 30 to 59 Days Past Due	0	0
Financing Receivable, Recorded Investment, 60 to 89 Days Past Due	0	0
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	0
Financing Receivable, Recorded Investment, Past Due	0	0
Financing Receivable, Recorded Investment, Current	5,076	5,070
Loans Receivable, Net	5,076	5,070
Commercial Loan [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, 30 to 59 Days Past Due	0	0
Financing Receivable, Recorded Investment, 60 to 89 Days Past Due	0	131
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	123	993
Financing Receivable, Recorded Investment, Past Due	123	1,124
Financing Receivable, Recorded Investment, Current	70,476	25,807
Loans Receivable, Net	70,599	26,931
Consumer Loan [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, 30 to 59 Days Past Due	0	2
Financing Receivable, Recorded Investment, 60 to 89 Days Past Due	1	2
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	1
Financing Receivable, Recorded Investment, Past Due	1	5
Financing Receivable, Recorded Investment, Current	433	133
Loans Receivable, Net	$ 434	$ 138

Financing receivables that are less than 60 days past due but more than 29 days past due.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7A

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953401-111524

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- Definition

Financing receivables that are less than 90 days past due but more than 59 days past due.

+ References

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- Definition

Financing receivables that are current.

+ References

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- Definition

Financing receivables that are equal to or greater than 90 days past due.

+ References

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- Definition

Recorded Investment in financing receivables that are past due at the balance sheet date.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans held for sale. Excludes loans and leases covered under loss sharing agreements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(a))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph a

-Article 9

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