INCOME TAXES - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Sep. 30, 2024
Deferred tax assets:
Bad debt reserves	$ 2,103	$ 2,491
Inventory reserves	8,219	7,086
Deferred compensation (equity compensation and defined benefit plans)	6,739	7,036
Compensation benefits	6,121	5,052
Insurance reserve	1,918	2,411
Restructuring reserve	826	2,616
Warranty reserve	4,392	5,130
Lease liabilities	46,454	47,824
Net operating loss	27,750	25,299
Tax credits	5,933	5,933
Research & development	10,329	4,510
Other reserves and accruals	5,160	5,167
Deferred tax assets, gross	125,944	120,555
Valuation allowance	(30,703)	(26,989)
Total deferred tax assets	95,241	93,566
Deferred tax liabilities:
Goodwill and intangibles	(99,174)	(126,523)
Property, plant and equipment	(19,872)	(19,903)
Right-of-use assets	(43,498)	(45,112)
Unremitted foreign earnings	(1,514)	(1,896)
Other	(1,068)	(723)
Total deferred tax liabilities	(165,126)	(194,157)
Net deferred tax liabilities	$ (69,885)	$ (100,591)

Amount of deferred tax assets attributable to bad debt reserves.

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Amount of deferred tax assets attributable to deferred compensation.

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Deferred Tax Assets, Leasing Arrangements

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Amount of deferred tax liability attributable to taxable temporary differences.

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

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary difference from in-process research and development cost acquired in business combination or from joint venture formation or both.

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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 a valuation allowances, of deferred tax assets attributable to deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from compensation and benefits costs.

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

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

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from estimated losses under self insurance.

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

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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 intangible assets including goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences from leasing arrangements.

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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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Amount of deferred tax liability attributable to taxable temporary differences from undistributed earnings of subsidiary and other recognized entity not within country of domicile. Includes, but is not limited to, other basis differences.

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