Fair Value Measurements Fair Value on a Recurring basis (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Mar. 31, 2014
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Mortgage servicing rights	$ 211us-gaap_ServicingAssetAtFairValueAmount	$ 265us-gaap_ServicingAssetAtFairValueAmount
Government National Mortgage Asscociation, AFS, Fair Value Disclosure	5,535	5,665
Federal Home Loan Mortgage Corp., AFS, Fair Value Disclosure	11,024	11,596
Federal National Mortgage Corporation, AFS, Fair Value Disclosure	11,083	10,431
Other	47	49
US Government Agency securities	56,535	52,189
Other Securities, AFS, Fair Value Disclosure	16,224	9,531
Available-for-sale	100,448us-gaap_AvailableForSaleSecurities	89,461us-gaap_AvailableForSaleSecurities
Assets, Fair Value Disclosure	100,659us-gaap_AssetsFairValueDisclosure	89,726us-gaap_AssetsFairValueDisclosure
Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Mortgage servicing rights	0	0
Government National Mortgage Asscociation, AFS, Fair Value Disclosure	0	0
Federal Home Loan Mortgage Corp., AFS, Fair Value Disclosure	0	0
Federal National Mortgage Corporation, AFS, Fair Value Disclosure	0	0
Other		0
US Government Agency securities	0	0
Other Securities, AFS, Fair Value Disclosure	0	0
Available-for-sale	0	0
Assets, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Mortgage servicing rights	0	0
Government National Mortgage Asscociation, AFS, Fair Value Disclosure	5,535	5,665
Federal Home Loan Mortgage Corp., AFS, Fair Value Disclosure	11,024	11,596
Federal National Mortgage Corporation, AFS, Fair Value Disclosure	11,083	10,431
Other	0	0
US Government Agency securities	56,535	52,189
Other Securities, AFS, Fair Value Disclosure	16,224	9,531
Available-for-sale	100,401	89,412
Assets, Fair Value Disclosure	100,401	89,412
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Mortgage servicing rights	211	265
Government National Mortgage Asscociation, AFS, Fair Value Disclosure	0	0
Federal Home Loan Mortgage Corp., AFS, Fair Value Disclosure	0	0
Federal National Mortgage Corporation, AFS, Fair Value Disclosure	0	0
Other	47	49
US Government Agency securities	0	0
Other Securities, AFS, Fair Value Disclosure	0	0
Available-for-sale	47	49
Assets, Fair Value Disclosure	$ 258	$ 314

Federal Home Loan Mortgage Corp., AFS, Fair Value Disclosure

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Federal National Mortgage Corporation, AFS, Fair Value Disclosure

+ References

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Government National Mortgage Asscociation, AFS, Fair Value Disclosure

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (aa)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562

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- Definition

The fair value as of the balance sheet date of firm holdings in debt obligations issued by the US government including short-term Treasury bills, medium-term Treasury notes, and long-term Treasury bonds, as well as debt issued by agencies. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 940

-SubTopic 320

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=29643736&loc=d3e42546-110969

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- Definition

Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as available-for-sale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Mortgage-Backed Securities

-URI http://asc.fasb.org/extlink&oid=6517959

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- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=7882072&loc=d3e122625-111746

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