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Income Taxes - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Dec. 29, 2019 | Dec. 30, 2018 | Sep. 29, 2019
Income Tax Disclosure [Abstract] |  |  |
Effective tax rate | 21.10% | 20.40% |
Tax Cuts And Jobs Act, change in tax rate, income tax benefit |  | $ 2.6 |
Effective income tax rate excluding excess tax benefit and TCJA impact |  | 25.30% |
Liability for uncertain tax positions | $ 9.6 |  | $ 9.2

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