Investment Securities Amortized Cost and Estimated Fair Value (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Jun. 30, 2012	Mar. 31, 2012
Schedule of Available-for-sale Securities [Line Items]
available for sale, at fair value	$ 90,833	$ 85,106
HTM Estimated Fair Value	11,091	11,774
Total securities amortized cost	100,953	95,821
Total securities gross unrealized gain	1,253	1,175
Total securities gross unrealized losses	(282)	(116)
Total securities Estimated Fair Value	101,924	96,880
Held-to-maturity Securities	10,401	11,081
Government National Mortgage Association
Schedule of Available-for-sale Securities [Line Items]
HTM Amortized Cost	6,202	6,659
HTM Gross Unrealized Gains	476	473
HTM Gross Unrealized Losses	0	0
HTM Estimated Fair Value	6,678	7,132
Federal Home Loan Mortgage Corporation
Schedule of Available-for-sale Securities [Line Items]
HTM Amortized Cost	2,637	2,794
HTM Gross Unrealized Gains	128	134
HTM Gross Unrealized Losses	0	0
HTM Estimated Fair Value	2,765	2,928
Federal National Mortgage Association
Schedule of Available-for-sale Securities [Line Items]
HTM Amortized Cost	1,562	1,628
HTM Gross Unrealized Gains	86	86
HTM Gross Unrealized Losses	0	0
HTM Estimated Fair Value	1,648	1,714
Held-to-maturity securities
Schedule of Available-for-sale Securities [Line Items]
HTM Amortized Cost	10,401	11,081
HTM Gross Unrealized Gains	690	693
HTM Gross Unrealized Losses	0	0
HTM Estimated Fair Value	11,091	11,774
Available-for-sale Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	90,552	84,740
AFS Gross Unrealized Gains	563	482
AFS Gross Unrealized Losses	(282)	(116)
available for sale, at fair value	90,833	85,106
Total mortgage-backed securities AFS
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	44,090	45,782
AFS Gross Unrealized Gains	352	327
AFS Gross Unrealized Losses	(241)	(25)
available for sale, at fair value	44,201	46,084
Government National Mortgage Association
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	27,138	31,100
AFS Gross Unrealized Gains	148	269
AFS Gross Unrealized Losses	(207)	(23)
available for sale, at fair value	27,079	31,346
Federal Home Loan Mortgage Corporation
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	8,180	7,468
AFS Gross Unrealized Gains	44	8
AFS Gross Unrealized Losses	(34)	(1)
available for sale, at fair value	8,190	7,475
Federal National Mortgage Association
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	6,694	7,214
AFS Gross Unrealized Gains	148	50
AFS Gross Unrealized Losses	0	(1)
available for sale, at fair value	6,842	7,263
Other
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	51	0
AFS Gross Unrealized Gains	0	0
AFS Gross Unrealized Losses	0	0
available for sale, at fair value	51	0
Small Business Association
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	2,027
AFS Gross Unrealized Gains	12
AFS Gross Unrealized Losses	0
available for sale, at fair value	2,039
US Government Agency Securities
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	30,976	23,176
AFS Gross Unrealized Gains	64	91
AFS Gross Unrealized Losses	(40)	(63)
available for sale, at fair value	31,000	23,204
US Government Securities
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	3,104	3,356
AFS Gross Unrealized Gains	5	6
AFS Gross Unrealized Losses	(1)	(1)
available for sale, at fair value	3,108	3,361
Corporate Bonds
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	1,897	1,890
AFS Gross Unrealized Gains	43	58
AFS Gross Unrealized Losses	0	0
available for sale, at fair value	1,940	1,948
Other
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost	10,485	10,536
AFS Gross Unrealized Gains	99	0
AFS Gross Unrealized Losses	0	(27)
available for sale, at fair value	$ 10,584	$ 10,509

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