Investment Securities Amortized Cost and Estimated Fair Value (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Dec. 31, 2012	Mar. 31, 2012	Mar. 31, 2011
Schedule of Available-for-sale Securities [Line Items]
AFS Fair Value	$ 109,936	$ 85,106
Held to maturity securities fair value	10,737		11,774
Total securities amortized cost	118,693	95,821
Total securities gross unrealized gain	1,658	1,175
Total securities gross unrealized losses	(224)	(116)
Total securities Estimated Fair Value	120,127	96,880
Held-to-maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
HTM Amortized Cost	9,565	11,081
HTM Gross Unrealized Gains	626	693
HTM Gross Unrealized Losses	0	0
Held to maturity securities fair value	10,191	11,774
Government National Mortgage Association
Schedule of Available-for-sale Securities [Line Items]
HTM Amortized Cost	5,660	6,659
HTM Gross Unrealized Gains	429	473
HTM Gross Unrealized Losses	0	0
Held to maturity securities fair value	6,089	7,132
Federal Home Loan Mortgage Corporation
Schedule of Available-for-sale Securities [Line Items]
HTM Amortized Cost	2,479	2,794
HTM Gross Unrealized Gains	114	134
HTM Gross Unrealized Losses	0	0
Held to maturity securities fair value	2,593	2,928
Federal National Mortgage Association
Schedule of Available-for-sale Securities [Line Items]
HTM Amortized Cost	1,426	1,628
HTM Gross Unrealized Gains	83	86
HTM Gross Unrealized Losses	0	0
Held to maturity securities fair value	1,509	1,714
Available-for-sale Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	109,128	84,740
AFS Gross Unrealized Gains	1,032	482
AFS Gross Unrealized Losses	(224)	(116)
AFS Fair Value	109,936	85,106
Total mortgage-backed securities AFS
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	34,551	45,782
AFS Gross Unrealized Gains	411	327
AFS Gross Unrealized Losses	(182)	(25)
AFS Fair Value	34,780	46,084
Government National Mortgage Association
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	23,019	31,100
AFS Gross Unrealized Gains	168	269
AFS Gross Unrealized Losses	(182)	(23)
AFS Fair Value	23,005	31,346
Federal Home Loan Mortgage Corporation
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	6,813	7,468
AFS Gross Unrealized Gains	107	8
AFS Gross Unrealized Losses	0	(1)
AFS Fair Value	6,920	7,475
Federal National Mortgage Association
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	4,669	7,214
AFS Gross Unrealized Gains	136	50
AFS Gross Unrealized Losses	0	(1)
AFS Fair Value	4,805	7,263
Other
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	50
AFS Gross Unrealized Gains	0
AFS Gross Unrealized Losses	0
AFS Fair Value	50
US Government Agency Securities
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	41,983	23,176
AFS Gross Unrealized Gains	309	91
AFS Gross Unrealized Losses	(42)	(63)
AFS Fair Value	42,250	23,204
US Government Securities
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	2,800	3,356
AFS Gross Unrealized Gains	2	6
AFS Gross Unrealized Losses	0	(1)
AFS Fair Value	2,802	3,361
Corporate Bonds
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	1,911	1,890
AFS Gross Unrealized Gains	111	58
AFS Gross Unrealized Losses	0	0
AFS Fair Value	2,022	1,948
Asset-backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	15,252
AFS Gross Unrealized Gains	97
AFS Gross Unrealized Losses	0
AFS Fair Value	15,349
Small Business Association [Member]
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	1,940
AFS Gross Unrealized Gains	39
AFS Gross Unrealized Losses	0
AFS Fair Value	1,979
Other
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	10,691	10,536
AFS Gross Unrealized Gains	63	0
AFS Gross Unrealized Losses	0	(27)
AFS Fair Value	$ 10,754	$ 10,509

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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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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Amount of investments in debt securities categorized as held-to-maturity valued at amortized cost, excludes other than temporary impairment (OTTI).

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The increase (decrease), resulting in a gain, in the difference between the fair value and the carrying value, or in the comparative fair values, of securities held at each balance sheet date, that was included in earnings for the period.

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