| Property and Equipment - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
| Sep. 30, 2012 | Sep. 30, 2011 | Sep. 30, 2012 | Sep. 30, 2011 | |
| Property, Plant and Equipment [Line Items] | ||||
| Depreciation expense | $ 31 | $ 53 | $ 57 | $ 117 | 
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- Definition The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
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- Details 
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