Employee Retirement Benefits (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended					12 Months Ended						9 Months Ended	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 Pension Benefits	Dec. 31, 2011 Pension Benefits	Dec. 31, 2012 U.S. Plan	Dec. 31, 2012 U.S. Plan Minimum	Dec. 31, 2012 U.S. Plan Maximum	Dec. 31, 2012 Other Pension Plans, Defined Benefit [Member]	Dec. 31, 2011 Other Pension Plans, Defined Benefit [Member]	Dec. 31, 2010 Other Pension Plans, Defined Benefit [Member]	Sep. 30, 2011 Pension Benefits - U.K.	Dec. 31, 2012 Pension Benefits - U.K.	Dec. 31, 2012 Key officer postretirement car benefit plan Minimum	Dec. 31, 2012 Defined Contribution Pension [Member]	Dec. 31, 2012 Defined Contribution Pension [Member] Maximum	Dec. 31, 2012 Equity Securities [Member] U.S. Plan	Dec. 31, 2012 Equity Securities [Member] Pension Benefits - U.K.	Dec. 31, 2012 Fixed Income Funds [Member] U.S. Plan	Dec. 31, 2012 Fixed Income Funds [Member] Pension Benefits - U.K.	Dec. 31, 2012 Cash and Cash Equivalents [Member] Pension Benefits - U.K.
Defined Benefit Plan Disclosure [Line Items]
Multiemployer Plans, Withdrawal Obligation	$ 23
Fixed Interest Rate, on Cash Balance Credits in Year 2012 and Later Years Percentage	3.00%
Employer Match Percentage															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
Pension benefits included in AOCI				109.8	99.6
Provisions charged to income									8.9	8.0	8.8
Defined Contribution Plan, Cost Recognized	18.6	18.0	14.8
Defined Benefit Plan, Target Plan Asset Allocations																	65.00%	79.00%	35.00%	9.00%	12.00%
Discretionary cash contributions to qualified pension plan												58.9	38.4
Expected Return on Plan Assets, Percent						7.60%							7.50%
Estimated Future Employer Contributions in Next Fiscal Year							$ 20.0	$ 30.0