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Income Taxes - Reconciliation of the Federal Statutory Tax Rate to the Total Tax Provision (Benefit) (Detail)	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Income Tax Disclosure [Abstract]
Federal income taxes computed at the statutory rate	21.00%	21.00%
State income taxes, net of federal benefit	1.20%	1.40%
Unrecognized tax benefits	5.80%	0.00%
Other, net	1.80%	(0.50%)
Effective income tax rate	29.80%	21.90%

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Effective income tax rate reconciliation unrecognized tax benefits.

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Percentage income tax of federal statutory tax rate.

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

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Percentage 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 other adjustments.

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Percentage 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 applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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