Goodwill and Intangible Assets, Net (Details) - USD ($) $ in Millions	3 Months Ended
	Jan. 03, 2016	Dec. 28, 2014	Sep. 27, 2015
Goodwill and Intangible Assets Disclosure [Line Items]
Amortizable intangible assets	$ 332.4		$ 357.8
Goodwill	1,139.3		1,139.3
Amortization of intangible assets	25.4	$ 23.6
Completed technology
Goodwill and Intangible Assets Disclosure [Line Items]
Amortizable intangible assets	223.7		238.0
Amortization of intangible assets	14.2	11.5
Customer relationships
Goodwill and Intangible Assets Disclosure [Line Items]
Amortizable intangible assets	108.2		119.1
Amortization of intangible assets	10.9	11.2
Backlog, Trade Name and Other [Member]
Goodwill and Intangible Assets Disclosure [Line Items]
Amortizable intangible assets	0.5		$ 0.7
Amortization of intangible assets	$ 0.3	$ 0.9