Income Taxes - Components of Deferred Tax Assets (Liabilities) (Detail) - USD ($) $ in Millions	Oct. 02, 2016	Sep. 27, 2015
Income Tax Disclosure [Abstract]
Accounts receivable, net	$ 2.1	$ 1.9
Inventories	18.8	17.5
Accrued employee benefit expenses	10.0	8.4
Net operating losses	216.1	164.6
Tax credits	238.0	153.5
Accrued other expenses	10.3	9.7
Deferred equity compensation	20.0	18.9
Property and equipment, net	(4.4)	(13.8)
Debt issuance costs	20.9	0.3
Other assets	12.3	11.1
Total deferred tax assets	552.9	399.7
Intangible assets	(176.8)	(137.1)
Foreign declared dividend	(2.5)	0.0
Total deferred tax liabilities	(179.3)	(137.1)
Less valuation allowance	(456.4)	(250.6)
Deferred tax assets (liabilities), net	$ 82.8
Deferred tax assets (liabilities), net		$ 12.0