Income Taxes (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 28, 2018	Dec. 29, 2017
Federal statutory income tax rate	21.00%
Employee service share-based compensation, tax benefit from compensation expense		$ 16.2
taxes payable, repatriation tax	$ 224.6
Repatriation of foreign earnings, amount		257.8
Cumulative Effect of New Accounting Principle in Period of Adoption		$ 18.5
Statutory tax rate due to change in legislation		24.60%
Accrued income taxes, current	71.6	$ 62.5
Accrued repatriation tax in long-term liabilities	206.6
Years One through Five [Member]
taxes payable, repatriation tax	18.0
Year Six [Member]
taxes payable, repatriation tax	33.6
Year Seven [Member]
taxes payable, repatriation tax	44.9
Year Eight [Member]
taxes payable, repatriation tax	$ 56.1

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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.

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Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all domestic and foreign income tax obligations due beyond one year or the operating cycle, whichever is longer. Alternate captions include income taxes payable, noncurrent.

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to repatriation of foreign earnings.

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