Employee Retirement Benefits (Details) (USD $) In Millions, unless otherwise specified		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended	6 Months Ended		12 Months Ended	6 Months Ended	3 Months Ended		6 Months Ended			12 Months Ended
	Jun. 30, 2012 plan	Jun. 30, 2012 Pension Benefits	Jun. 30, 2011 Pension Benefits	Jun. 30, 2012 Pension Benefits	Jun. 30, 2011 Pension Benefits	Jun. 30, 2012 Pension Benefits - U.S.	Jun. 30, 2011 Pension Benefits - U.S.	Jun. 30, 2012 Pension Benefits - U.S.	Jun. 30, 2011 Pension Benefits - U.S.	Jun. 30, 2012 Pension Benefits - Non-U.S.	Jun. 30, 2011 Pension Benefits - Non-U.S.	Jun. 30, 2012 Pension Benefits - Non-U.S.	Jun. 30, 2011 Pension Benefits - Non-U.S.	Jun. 30, 2011 Pension Benefits - U.K.	Jun. 30, 2012 Pension Benefits - U.K.	Jun. 30, 2011 Pension Benefits - U.K.	Dec. 31, 2011 Pension Benefits - U.K.	Jun. 30, 2012 Pension Benefits - U.K. Maximum	Jun. 30, 2012 Postretirement Benefits (U.S.)	Jun. 30, 2011 Postretirement Benefits (U.S.)	Jun. 30, 2012 Postretirement Benefits (U.S.)	Jun. 30, 2011 Postretirement Benefits (U.S.)	Jun. 30, 2012 Key officer postretirement car benefit plan	Dec. 31, 2011 Key officer postretirement car benefit plan Minimum
Components of Net Periodic Benefit Cost:
Service cost						$ 7.0	$ 6.9	$ 13.3	$ 13.1	$ 0.3	$ 1.8	$ 0.6	$ 3.5						$ 0.1		$ 0.2	$ 0.1
Interest cost						7.4	7.5	13.9	14.0	2.3	2.8	4.6	5.6						0.2	0.3	0.4	0.5
Expected return on plan assets						(8.0)	(8.1)	(15.3)	(15.2)	(3.0)	(3.1)	(6.0)	(6.2)
Net amortizations						3.2	2.3	6.0	4.3	(0.1)	(0.3)	(0.1)	(0.6)							0.1		0.1
Settlement loss							0.4		0.7
Curtailment gain											(13.1)		(13.1)
Net pension/postretirement expense						9.6	9.0	17.9	16.9	(0.5)	(11.9)	(0.9)	(10.8)						0.3	0.4	0.6	0.7
Other disclosures
Number of multiemployer plans with significant underfunded liabilities	1
Company contributions		11.8	12.3	32.2	57.1
Discretionary cash contributions to qualified pension plan														0.8	3.2	13.2
Employer's matching contribution as percentage of employee contributions															100.00%
Percentage of employee contributions eligible for employer match																		8.00%
The period of enhanced employer matching contributions															5 years
Unamortized prior service cost																	$ 13.1
Service period																								20 years
Retirement age																								58 years
Term of available benefit until participant reaches a specific age																							15 years
Eligible age for car benefit																							80 years