| Intangible Assets - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified | 6 Months Ended | 12 Months Ended | |
|---|---|---|---|
| Sep. 30, 2012 | Sep. 30, 2011 | Mar. 31, 2012 | |
| Finite-Lived Intangible Assets [Line Items] | |||
| Increase In Intangible Assets | $ 4,489 | ||
| Unamortizable Intangible Assets, Impairment of intangibles | 2,319 | ||
| Amortization expense for continuing operations, in cost of revenues | $ 116 | $ 116 | |
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- Definition Amortization of property, plant and equipment directly related to goods produced and sold and services rendered by an entity during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Details 
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- Definition The increase (decrease) during the reporting period in intangible assets (for example patents and licenses). Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Impairment recognized during the period and allocated to the reportable segment that results from the write-down of indefinite-lived intangible assets after comparing the implied fair value of reporting unit indefinite-lived intangible assets with the carrying amount of that indefinite-lived intangible assets, which are assessed at least annually for impairment. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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