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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Sep. 30, 2016 | Sep. 30, 2015
Income Tax Disclosure [Abstract] |  |
Valuation allowance against deferred tax assets | 100.00% |
Gross federal net operating loss carry forwards |  | $ 185.1
Gross federal estimated net operating loss carry forwards | $ 78.7 |
Gross state net operating loss carry forwards |  | $ 285.4
Gross state estimated net operating loss carry forwards | $ 133.9 |

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- Definition Federal estimated net operating loss carry forward. + References No definition available. + Details
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- Definition Federal net operating loss carry forward. + References No definition available. + Details
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- Definition Percentage of valuation allowance. + References No definition available. + Details
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- Definition State estimated net operating Loss carry forward. + References No definition available. + Details
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