Inventory (Schedule Of Inventories) (Details) - USD ($) $ in Millions	Dec. 28, 2018	Sep. 28, 2018
Inventory, Net [Abstract]
Raw materials	$ 21.5	$ 20.2
Work-in-process	301.5	340.7
Finished goods	162.5	124.8
Finished goods held on consignment by customers	7.6	4.5
Total inventory	$ 493.1	$ 490.2