Segment Information (Geographic Revenue) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Sep. 28, 2018	Jun. 29, 2018	Mar. 30, 2018	Dec. 29, 2017	Sep. 29, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 30, 2016	Sep. 28, 2018	Sep. 29, 2017	Sep. 30, 2016
Segment Reporting Information [Line Items]
Net revenue	$ 1,008.4	$ 894.3	$ 913.4	$ 1,051.9	$ 984.6	$ 900.8	$ 851.7	$ 914.3	$ 3,868.0	$ 3,651.4	$ 3,289.0
Total Americas [Member]
Segment Reporting Information [Line Items]
Net revenue									1,946.2	1,615.4	1,455.0
China
Segment Reporting Information [Line Items]
Net revenue									982.8	1,018.8	971.2
South Korea
Segment Reporting Information [Line Items]
Net revenue									432.7	531.8	393.0
TAIWAN, PROVINCE OF CHINA
Segment Reporting Information [Line Items]
Net revenue									339.1	335.4	323.6
Asia, Other [Member]
Segment Reporting Information [Line Items]
Net revenue									22.6	32.6	44.1
Europe, Middle East and Africa [Member]
Segment Reporting Information [Line Items]
Net revenue									$ 144.6	$ 117.4	$ 102.1