Income Taxes - Components of Deferred Tax Asset (Detail) - USD ($) $ in Thousands	Sep. 30, 2025	Sep. 30, 2024
Deferred tax assets:
Inventories	$ 2,233	$ 2,994
Operating lease liabilities	32,741	31,280
Accrued expenses	1,140	2,214
Stock-based compensation	4,660	5,756
Interest deductions	8,490	520
US tax effect of foreign taxes	5,298	3,999
Tax loss carryforwards	4,135	3,315
Other	4,725	2,724
Valuation allowance	0
Total long-term deferred tax assets	63,422	52,802
Deferred tax liabilities:
Depreciation and amortization	(73,348)	(72,133)
Operating lease right-of-use assets	(31,182)	(33,225)
Equity method investments	(3,159)	(3,531)
Other	(3,180)	(4,230)
Total long-term deferred tax liabilities	(110,869)	(113,119)
Net deferred tax liabilities	$ (47,447)	$ (60,317)

Deferred tax assets operating lease right of use assets.

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Deferred tax liabilities operating lease liabilities.

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Amount of deferred tax liability attributable to taxable temporary differences.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible interest carryforward.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from inventory.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible foreign tax credit carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from accrued liabilities.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.

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Amount of deferred tax liability attributable to taxable temporary differences from investments (excludes investments in subsidiaries and equity method investments).

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Amount of deferred tax liability attributable to taxable temporary differences classified as other.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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