Goodwill and Intangible Assets (Tables)

12 Months Ended

Sep. 29, 2017

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Goodwill

The changes to the carrying amount of goodwill are as follows (in millions):

	As of
	September 29, 2017		September 30, 2016
Goodwill at beginning of the period	$	873.3	$	856.7
Goodwill recognized through business combinations (Note 3)	9.7		16.6
Goodwill adjustments	—		—
Goodwill impairment	—		—
Goodwill at the end of the period	$	883.0	$	873.3

Schedule Of Intangible Assets Excluding Goodwill

Intangible assets consist of the following (in millions):

		As of							As of
	Weighted average amortization period (years)	September 29, 2017							September 30, 2016
		Gross carrying amount		Accumulated amortization			Net carrying amount		Gross carrying amount		Accumulated amortization			Net carrying amount
Customer relationships	5.0	$	78.5	$	(63.4	)	$	15.1	$	78.5	$	(57.7	)	$	20.8
Developed technology and other	5.0	150.2		(110.9		)	39.3		133.8		(89.2		)	44.6
Trademarks	3.0	1.6		(0.3		)	1.3		1.6		—			1.6
Internally developed software	3.0	12.1		—			12.1		—		—			—
Total intangible assets		$	242.4	$	(174.6	)	$	67.8	$	213.9	$	(146.9	)	$	67.0

Schedule of Expected Amortization Expense

Annual amortization expense for the next five fiscal years related to intangible assets is expected to be as follows (in millions):

	2018		2019		2020		2021		2022		Thereafter
Amortization expense	$	19.8	$	18.1	$	15.4	$	8.5	$	0.5	$	5.5