Fair Value Measurements - Foreclosed Assets Remeasured and Reported at Fair Value (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreclosed Assets Remeasured at Initial Recognition Carrying Value Of Foreclosed Assets Prior To Remeasurement	$ 67	$ 2,198
Foreclosed Assets Remeasured at Initial Recognition Charge-offs recognized in the allowance for loan losses	0	(204)
Fair Value of Foreclosed Assets Remeasured at Initial Recognition	67	1,994
Foreclosed Assets Remeasured Subsequent to initial Recognition Carrying value of foreclosed assets prior to remeasurement	138	499
Foreclosed Assets Remeasured Subsequent to Initial Write-downs included in other non-interest expense	(22)	(244)
Fair Value of Foreclosed Assets remeasured subsequent to initial recognition	$ 116	$ 255

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Fair Value of Foreclosed Assets remeasured subsequent to initial recognition

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Foreclosed Assets Remeasured at Initial Recognition Charge Offs Recognized In Allowance For Loan Losses

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Foreclosed Assets Remeasured Subsequent to initial recognition Write-downs included in other non-interest expense

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