Restructuring and Severance Charges - Restructuring Activities and Accrued Liabilities (Details) $ in Millions	3 Months Ended
	Jan. 01, 2017 USD ($)
Restructuring Reserve [Roll Forward]
Beginning Balance	$ 7.5
Provisions	2.4
Cash expenditures	(2.1)
Ending Balance	7.8
Employee Severance
Restructuring Reserve [Roll Forward]
Beginning Balance	2.5
Provisions	2.3
Cash expenditures	(1.3)
Ending Balance	3.5
Contract Termination Costs
Restructuring Reserve [Roll Forward]
Beginning Balance	4.6
Provisions	0.1
Cash expenditures	(0.7)
Ending Balance	4.0
Other Associated Costs
Restructuring Reserve [Roll Forward]
Beginning Balance	0.4
Provisions	0.0
Cash expenditures	(0.1)
Ending Balance	$ 0.3