Summary of Significant Accounting Policies (Details) - USD ($)	12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Significant Accounting Policies [Line Items]
Foreign currency gain (loss)	$ 2,000,000.0	$ 1,900,000	$ 1,700,000
Software amortization	3,900,000	4,300,000	5,000,000.0
Depreciation	53,800,000	52,700,000	55,600,000
Reserve for Sales Returns, Current	42,800,000	50,300,000
Customer advance payments	800,000	1,100,000
Advertising expense	$ 126,300,000	$ 127,100,000	$ 116,000,000.0
Supplier Finance Program, Obligation, Statement of Financial Position [Extensible Enumeration]	Other liabilities	Other current liabilities
Loans Receivable with Variable Rates of Interest	$ 140,000,000.0
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Significant Accounting Policies [Line Items]
Vesting period (in years)	3 years
Minimum | Capitalized software costs
Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	3 years
Minimum | Machinery and equipment
Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	3 years
Minimum | Buildings and building improvements
Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	15 years
Minimum | RSE awards
Significant Accounting Policies [Line Items]
Vesting period (in years)	3 years
Maximum | Capitalized software costs
Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life		7 years
Maximum | Machinery and equipment
Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	10 years
Maximum | Buildings and building improvements
Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life		30 years
Maximum | RSE awards
Significant Accounting Policies [Line Items]
Vesting period (in years)	4 years