Retirement Plans (Schedule of Net Periodic Benefit Cost) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 25, 2015	Sep. 26, 2014	Sep. 27, 2013
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 4.5	$ 5.1	$ 5.0
Interest cost	17.5	19.6	18.2
Expected return on plan assets	(22.6)	(24.6)	(29.6)
Amortization of net actuarial loss	9.4	8.1	12.3
Amortization of prior service cost	(0.6)	(0.6)	0.6
Loss on plan settlements	6.0	3.8	6.8
Net period benefit cost (credit)	$ 14.2	11.4	13.3
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Allocation of total pension plan assets	70.60%
Allocation of total projected benefit obligation	73.10%
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0.1	0.1	0.1
Interest cost	1.9	2.1	2.4
Expected return on plan assets	0.0	0.0	0.0
Amortization of net actuarial loss	0.0	0.0	0.3
Amortization of prior service cost	(4.0)	(9.3)	(9.1)
Loss on plan settlements	0.0	0.0	0.0
Net period benefit cost (credit)	$ (2.0)	$ (7.1)	$ (6.3)