Pensions and Postretirement Benefits (Details 5) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Components of net periodic benefit cost (Income) :
Service cost	$ 1.1	$ 1.1	$ 1.4
Interest cost	15.6	17.4	19.6
Curtailment (gain)/ loss	1.4
Special termination benefit charge	4.0
Weighted average assumptions used to determine net periodic benefit cost
Discount rate	5.29%	5.55%	6.38%
U.S. Plans [Member]
Components of net periodic benefit cost (Income) :
Service cost	49.1	46.3	42.9
Interest cost	171.2	168.5	171.9
Expected return on plan assets	(209.6)	(187.6)	(174.2)
Amortization of prior service cost	5.9	7.0	7.3
Amortization of actuarial (gain) loss	59.5	116.8	105.1
Gross periodic benefit cost (income)	76.1	151.0	153.0
Settlement (gain)/ loss	0.4
Curtailment (gain)/ loss	1.4
Net benefit cost (income)	77.9	151.0	153.0
Special termination benefit charge	4.0
Weighted average assumptions used to determine net periodic benefit cost
Expected long-term rate of return on assets	8.25%	8.75%	8.75%
Rate of compensation increase	4.10%	4.10%	4.10%
U.K. Plans [Member]
Components of net periodic benefit cost (Income) :
Service cost	17.1	15.6	16.0
Interest cost	42.0	39.0	37.2
Expected return on plan assets	(61.4)	(52.5)	(42.6)
Amortization of prior service cost	(0.6)	(0.6)	(0.6)
Amortization of actuarial (gain) loss	0.1	2.6	7.4
Gross periodic benefit cost (income)	(2.8)	4.1	17.4
Net benefit cost (income)	(2.8)	4.1	17.4
Special termination benefit charge	0.7	0.1	1.2
Weighted average assumptions used to determine net periodic benefit cost
Expected long-term rate of return on assets	8.25%	8.50%	8.50%
Rate of compensation increase	3.75%	3.75%	3.75%
Other Plans [Member]
Components of net periodic benefit cost (Income) :
Service cost	7.4	4.9	3.9
Interest cost	8.4	7.1	6.6
Expected return on plan assets	(8.4)	(7.0)	(5.2)
Amortization of prior service cost	0.4	0.1	0.9
Amortization of actuarial (gain) loss	2.6	1.5	1.3
Gross periodic benefit cost (income)	10.4	6.6	7.5
Settlement (gain)/ loss	0.3		(0.4)
Net benefit cost (income)	$ 10.7	$ 6.6	$ 7.1
Weighted average assumptions used to determine net periodic benefit cost
Expected long-term rate of return on assets	8.08%	8.32%	8.12%
Rate of compensation increase	3.41%	3.38%	3.31%
Discount Rate 1/1 - 6/6 [Member] | U.S. Plans [Member]
Weighted average assumptions used to determine net periodic benefit cost
Discount rate	5.67%	5.90%	6.47%
Discount Rate 1/1 - 6/6 [Member] | U.K. Plans [Member]
Weighted average assumptions used to determine net periodic benefit cost
Discount rate	5.81%	5.88%	5.88%
Discount Rate 1/1 - 6/6 [Member] | Other Plans [Member]
Weighted average assumptions used to determine net periodic benefit cost
Discount rate	5.20%	5.75%	6.17%
Discount Rate 6/7 - 10/5 [Member] | U.S. Plans [Member]
Weighted average assumptions used to determine net periodic benefit cost
Discount rate	5.63%	5.90%	6.47%
Discount Rate 6/7 - 10/5 [Member] | U.K. Plans [Member]
Weighted average assumptions used to determine net periodic benefit cost
Discount rate	5.81%	5.88%	5.88%
Discount Rate 6/7 - 10/5 [Member] | Other Plans [Member]
Weighted average assumptions used to determine net periodic benefit cost
Discount rate	5.20%	5.75%	6.17%
Discount Rate 10/6 - 12/31 [Member] | U.S. Plans [Member]
Weighted average assumptions used to determine net periodic benefit cost
Discount rate	5.63%	5.90%	6.47%
Discount Rate 10/6 - 12/31 [Member] | U.K. Plans [Member]
Weighted average assumptions used to determine net periodic benefit cost
Discount rate	5.81%	5.88%	5.88%
Discount Rate 10/6 - 12/31 [Member] | Other Plans [Member]
Weighted average assumptions used to determine net periodic benefit cost
Discount rate	5.17%	5.75%	6.17%