Supplemental Balance Sheet Information - USD ($)	Sep. 30, 2024	Sep. 30, 2023
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid Expense, Current	$ 76,400,000	$ 72,500,000
Value Added Tax Receivable, Current	40,000,000.0	43,700,000
Income Taxes Receivable, Current	14,700,000	18,900,000
Other Assets, Current	9,100,000	12,300,000
Other current assets	140,200,000	147,400,000
Other Liabilities, Current [Abstract]
Accrued advertising, sales promotion and allowances	26,300,000	31,500,000
Accrued Trade Allowance, Current	28,700,000	29,800,000
Accrued salaries, vacations and incentive compensation	(78,600,000)	(65,400,000)
Reserve for Sales Returns, Current	50,300,000	53,500,000
Accrued interest	(24,700,000)	(25,000,000.0)
Taxes Payable	13,600,000	11,900,000
Other	97,600,000	92,400,000
Other current liabilities	319,800,000	309,500,000
Other Liabilities, Noncurrent [Abstract]
Liability, Defined Benefit Plan, Noncurrent	45,600,000	58,200,000
Other Accrued Liabilities, Noncurrent	129,400,000	121,500,000
Other Liabilities, Noncurrent	$ 175,000,000.0	$ 179,700,000