Fair Value Measurements Fair Value on a Recurring basis (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Mar. 31, 2012
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Servicing Asset at Amortized Cost	$ 275	$ 491
US Treasuries, AFS, Fair Value Disclosure		3,361
Government National Mortgage Asscociation, AFS, Fair Value Disclosure	23,840	27,612
Federal Home Loan Mortgage Corp., AFS, Fair Value Disclosure	16,059	5,305
Federal National Mortgage Corporation, AFS, Fair Value Disclosure	4,303	6,141
Corporate Securities, AFS, Fair Value Disclosure		1,949
Other Securities, AFS, Fair Value Disclosure	56,330	40,738
AFS Fair Value	116,051	85,106
Assets, Fair Value Disclosure	125,680	96,880
Asset-Backed Securities, at Carrying Value	15,519
Investments, Fair Value Disclosure	116,326	85,597
Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Servicing Asset at Amortized Cost	0	0
US Treasuries, AFS, Fair Value Disclosure		3,361
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
Corporate Securities, AFS, Fair Value Disclosure		0
Other Securities, AFS, Fair Value Disclosure	0	0
AFS Fair Value	0	3,361
Assets, Fair Value Disclosure	0	3,361
Asset-Backed Securities, at Carrying Value	0
Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Servicing Asset at Amortized Cost	0	0
US Treasuries, AFS, Fair Value Disclosure		0
Government National Mortgage Asscociation, AFS, Fair Value Disclosure	23,840	27,612
Federal Home Loan Mortgage Corp., AFS, Fair Value Disclosure	16,059	5,305
Federal National Mortgage Corporation, AFS, Fair Value Disclosure	4,303	6,141
Corporate Securities, AFS, Fair Value Disclosure		1,949
Other Securities, AFS, Fair Value Disclosure	56,279	40,686
AFS Fair Value	116,000	81,693
Assets, Fair Value Disclosure	116,000	81,693
Asset-Backed Securities, at Carrying Value	15,519
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Servicing Asset at Amortized Cost	275	491
US Treasuries, AFS, Fair Value Disclosure		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
Corporate Securities, AFS, Fair Value Disclosure		0
Other Securities, AFS, Fair Value Disclosure	51	52
AFS Fair Value	51	52
Assets, Fair Value Disclosure	326	543
Asset-Backed Securities, at Carrying Value	$ 0

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Federal National Mortgage Corporation, AFS, Fair Value Disclosure

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Other Securities, AFS, Fair Value Disclosure

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- Definition

Investments in notes or bonds that are collateralized by a specific group of underlying assets owned by the issuer of the notes or bonds which are short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 8, 9

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- Definition

This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

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-Paragraph 1

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Available-for-Sale Securities

-URI http://asc.fasb.org/extlink&oid=6505594

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-Glossary Trading Securities

-URI http://asc.fasb.org/extlink&oid=6526789

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-Number 210

-Section 03

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Amortized carrying amount (balance) as of the balance sheet date of an asset representing net future revenues from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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