Loan Receivable and Allowance for Loan and Lease Losses Non performing TDRs (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Sep. 30, 2012	Sep. 30, 2012	Mar. 31, 2012
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Impaired, Nonperforming, Nonaccrual of Interest	$ 34,953	$ 34,953	$ 54,588
Mortgage Loans on Real Estate, Number of Loans	6	7
Pre-modifcation Outstanding Recorded Investment		4,123
Financing Receivable, Modifications, Nature and Extent of Transaction		3248000
Financing Receivable, Modifications, Pre-Modification Recorded Investment	3,583	3,583
Financing Receivable, Recorded Investment, Current	2,708	2,708
One- to four family loans [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Impaired, Nonperforming, Nonaccrual of Interest	6,094	6,094	6,988
Multifamily Loans [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Impaired, Nonperforming, Nonaccrual of Interest	1,724	1,724	2,923
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Impaired, Nonperforming, Nonaccrual of Interest	14,145	14,145	24,467
Construction Loans [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Impaired, Nonperforming, Nonaccrual of Interest	4,258	4,258	11,325
Commercial Loan [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Impaired, Nonperforming, Nonaccrual of Interest	8,717	8,717	8,862
Consumer Loan [Member]
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Impaired, Nonperforming, Nonaccrual of Interest	15	15	23
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Mortgage Loans on Real Estate, Number of Loans	1	2
Pre-modifcation Outstanding Recorded Investment		466
Financing Receivable, Modifications, Nature and Extent of Transaction		466
Financing Receivable, Modifications, Pre-Modification Recorded Investment	466	466
Financing Receivable, Recorded Investment, Current	466	466
weighted average rate pre modification	12.02%	6.55%
Weighted average rate post modification	12.02%	6.07%
Consumer Loan [Member]
Financing Receivable, Modifications [Line Items]
Mortgage Loans on Real Estate, Number of Loans	4	4
Pre-modifcation Outstanding Recorded Investment		2,242
Financing Receivable, Modifications, Nature and Extent of Transaction		2242
Financing Receivable, Modifications, Pre-Modification Recorded Investment	2,242	2,242
Financing Receivable, Recorded Investment, Current	2,242	2,242
weighted average rate pre modification	7.44%	7.44%
Weighted average rate post modification	7.44%	7.44%
One- to four family loans [Member]
Financing Receivable, Modifications [Line Items]
Mortgage Loans on Real Estate, Number of Loans	1
Pre-modifcation Outstanding Recorded Investment		1,415
Financing Receivable, Modifications, Nature and Extent of Transaction		540
Financing Receivable, Modifications, Pre-Modification Recorded Investment	875	875
Financing Receivable, Recorded Investment, Current	$ 0	$ 0
weighted average rate pre modification	8.13%
Weighted average rate post modification	8.13%

Pre-modifcation Outstanding Recorded Investment

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Weighted average rate post modification on TDR loans

+ References

No definition available.

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weighted average rate pre modification rates on TDR loans

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- Definition

Description of the nature and the extent of troubled debt restructurings related to financing receivables.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 32

-URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953670-111524

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings before the financing receivable has been modified.

+ References

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- Definition

Financing receivables that are current.

+ References

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=6965416&loc=SL6953401-111524

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- Definition

Reflects the carrying amount of loans deemed to be questionable as to collection on which no interest is continuing to be recognized.

+ References

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

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 01-6

-Paragraph 13

-Subparagraph g

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Indicates the number of mortgages under each classification.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 948

-SubTopic 310

-Section S99

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