Income Taxes - Schedule of Reconciliation between Effective Tax Rate Income from Continuing Operations and Statutory Rate (Detail) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Income Tax Expense (Benefit), Effective Income Tax Rate Reconciliation, Amount [Abstract]
Income tax (benefit) provision at federal statutory rate	$ (26,555)	$ (49,280)	$ 4,707
(Reduction) increase in income taxes resulting from:
State taxes, net of federal tax benefit	(2,062)	(3,953)	669
Nondeductible stock compensation expenses	313	251	(241)
Permanent items	225	206	292
Change in valuation allowances	18,201	(22)	(140)
162(m) limitation	285	11	12
Impact of changing rates on deferred tax assets	499	(247)	509
Expired tax attributes	200	964	152
Other	149	80	(132)
(Benefit) provision for income taxes	$ (8,745)	$ (51,990)	$ 5,828

Income tax reconciliation compensation limitation.

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Income tax reconciliation expired tax attributes.

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Income tax reconciliation increases reductions in tax resulting from.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

+ References

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for award under share-based payment arrangement. Includes, but is not limited to, expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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