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Income Taxes - Additional Information (Detail) - USD ($) | 12 Months Ended
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Sep. 30, 2021 | Sep. 30, 2020
Income Tax Disclosure [Abstract] |  |
Valuation allowance against deferred tax assets | 100.00% |
Gross federal net operating loss carry forwards | $ 569,000,000.0 |
Gross state net operating loss carry forwards | 626,500,000 |
Unrecognized tax benefits | 0 | $ 0
Unrecognized tax benefits, penalties related to uncertain tax positions | 0 | 0
Unrecognized tax benefits, interest related to uncertain tax positions | $ 0 | $ 0

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- Definition State net operating loss carry forwards. + References No definition available. + Details
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- Definition Amount of unrecognized tax benefits. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 10B -URI http://asc.fasb.org/extlink&oid=123427490&loc=SL37586934-109318 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121826272&loc=SL6600010-109319 + Details
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- Definition Amount of interest expense for an underpayment of income taxes. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32718-109319 + Details
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