Supplemental Balance Sheet Information (Details) - USD ($) $ in Millions |
Jun. 30, 2026 |
Sep. 30, 2025 |
|---|---|---|
| Prepaid Expense and Other Assets, Current [Abstract] | ||
| Prepaid Expense, Current | $ 72.3 | $ 69.8 |
| Value Added Tax Receivable, Current | 53.6 | 43.7 |
| Income Taxes Receivable, Current | 15.7 | 13.3 |
| Other Assets, Current | 20.9 | 11.8 |
| Other current assets | 162.5 | 138.6 |
| Other Liabilities, Current [Abstract] | ||
| Accrued Advertising, Current | 41.4 | 23.6 |
| Accrued Trade Allowance, Current | 20.3 | 27.6 |
| Employee-related Liabilities, Current | 55.1 | 52.9 |
| Accrued Income Taxes, Current | 30.9 | 20.3 |
| Reserve for Sales Returns, Current | 45.1 | 42.8 |
| Interest Payable, Current | 9.3 | 24.7 |
| Other Accrued Liabilities, Current | 129.4 | 102.5 |
| Other current liabilities | 338.7 | 311.1 |
| Other Liabilities, Noncurrent [Abstract] | ||
| Liability, Defined Benefit Plan, Noncurrent | 26.2 | 32.7 |
| Other Accrued Liabilities, Noncurrent | 121.1 | 102.9 |
| Other Liabilities, Noncurrent | 147.3 | 135.6 |
| Restructuring Reserve, Current | $ 7.2 | $ 16.7 |
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- Definition Accrued Trade Allowance, Current No definition available.
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- Definition Reserve for Sales Returns, Current No definition available.
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- Definition Carrying value as of the balance sheet date of obligations incurred through that date and payable for advertising of the entity's goods and services. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all currently due domestic and foreign income tax obligations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Carrying amount due within one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of expenses incurred but not yet paid classified as other, due after one year or the normal operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of current assets classified as other. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of liabilities classified as other, due within one year or the normal operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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- Definition Amount of asset related to consideration paid in advance for costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Carrying amount as of the balance sheet date of value added taxes due either from customers arising from sales on credit terms, or as previously overpaid to tax authorities. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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