Property, Plant and Equipment (Schedule Of Property, Plant And Equipment) (Details) - USD ($) $ in Millions	Dec. 27, 2019	Sep. 27, 2019
Property, Plant and Equipment
Total property, plant and equipment, gross	$ 2,945.3	$ 2,883.9
Accumulated depreciation	(1,754.5)	(1,678.3)
Total property, plant and equipment, net	1,190.8	1,205.6
Land and improvements [Member]
Property, Plant and Equipment
Total property, plant and equipment, gross	11.8	11.7
Building and improvements [Member]
Property, Plant and Equipment
Total property, plant and equipment, gross	392.0	354.4
Furniture and fixtures [Member]
Property, Plant and Equipment
Total property, plant and equipment, gross	38.0	33.8
Machinery and equipment [Member]
Property, Plant and Equipment
Total property, plant and equipment, gross	2,346.6	2,311.5
Construction in progress [Member]
Property, Plant and Equipment
Total property, plant and equipment, gross	$ 157.0	$ 172.5