Pension and Other Postretirement Benefits (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 26, 2011
Net periodic pension costs under retirement plans and other postretirement benefits:
Expected total defined benefit plan employer contributions for fiscal year 2011	$ 60.0
Defined Benefit Plans
Net periodic pension costs under retirement plans and other postretirement benefits:
Service cost - benefits earned during the period	4.2	4.7
Interest cost on projected benefit obligation	41.1	45.1
Expected return on plan assets	(43.5)	(49.8)
Amortization of prior service cost (gain)	0.2	0.2
Amortization of net actuarial loss (gain)	9.8	5.0
Less expected participant contributions	0.4	(0.4)
Curtailment loss		0
Net periodic pension and postretirement benefit cost	11.4	4.8
Canada Defined Benefit Plans
Net periodic pension costs under retirement plans and other postretirement benefits:
Service cost - benefits earned during the period	4.1	4.7
Interest cost on projected benefit obligation	16.6	18.1
Expected return on plan assets	(15.3)	(18.6)
Amortization of prior service cost (gain)	0.2	0.2
Amortization of net actuarial loss (gain)	5.4	2.3
Less expected participant contributions	0.4	(0.4)
Curtailment loss		0
Net periodic pension and postretirement benefit cost	10.6	6.3
Contributions paid to defined benefit plans	7.5
U.S. Benefit Plans
Net periodic pension costs under retirement plans and other postretirement benefits:
Interest cost on projected benefit obligation	0	0.1
Net periodic pension and postretirement benefit cost	0	0.1
U.K. Defined Benefit Plans
Net periodic pension costs under retirement plans and other postretirement benefits:
Interest cost on projected benefit obligation	24.5	26.9
Expected return on plan assets	(28.2)	(31.2)
Amortization of net actuarial loss (gain)	4.4	2.7
Net periodic pension and postretirement benefit cost	0.7	(1.6)
MCI
Net periodic pension costs under retirement plans and other postretirement benefits:
Service cost - benefits earned during the period	0.1
Net periodic pension and postretirement benefit cost	0.1
Contributions paid to defined benefit plans	0.4
Other Postretirement Benefits
Net periodic pension costs under retirement plans and other postretirement benefits:
Service cost - benefits earned during the period	0.7	0.6
Interest cost on projected benefit obligation	2.0	1.9
Amortization of prior service cost (gain)	(0.9)	(0.9)
Amortization of net actuarial loss (gain)	(0.1)	(0.9)
Net periodic pension and postretirement benefit cost	1.7	0.7
Canada Other Postretirement Benefits
Net periodic pension costs under retirement plans and other postretirement benefits:
Service cost - benefits earned during the period	0.6	0.5
Interest cost on projected benefit obligation	2.0	1.9
Amortization of prior service cost (gain)	(0.9)	(0.9)
Amortization of net actuarial loss (gain)	(0.1)	(0.9)
Net periodic pension and postretirement benefit cost	1.6	0.6
U.S. Other Postretirement Benefits
Net periodic pension costs under retirement plans and other postretirement benefits:
Service cost - benefits earned during the period	0.1	0.1
Net periodic pension and postretirement benefit cost	$ 0.1	$ 0.1