Income Taxes (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Dec. 29, 2017	Jun. 28, 2019	Jun. 29, 2018
Federal statutory income tax rate		21.00%	24.60%
Repatriation of foreign earnings, amount	$ 238.0
Cumulative Effect of New Accounting Principle in Period of Adoption	$ 18.5
Accrued income taxes, current		$ 26.2	$ 43.8
Accrued Income Taxes, Noncurrent		188.6	$ 206.6
Years One through Four [Member] [Domain]
taxes payable, repatriation tax		18.0
Year Five [Member] [Domain]
taxes payable, repatriation tax		33.6
Year Six [Member]
taxes payable, repatriation tax		44.9
Years One through Five [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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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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