Pensions and Other Postretirement Benefits - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended								12 Months Ended
	Dec. 31, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2011 Pension Benefits, U.S. Plans	Dec. 31, 2010 Pension Benefits, U.S. Plans	Dec. 31, 2011 United Kingdom, Pounds	Dec. 31, 2010 United Kingdom, Pounds	Dec. 31, 2011 Other Postretirement Benefit Plans	Dec. 31, 2010 Other Postretirement Benefit Plans	Dec. 31, 2009 Other Postretirement Benefit Plans	Dec. 31, 2011 Pension Benefits, Non U.S. Plans	Dec. 31, 2010 Pension Benefits, Non U.S. Plans	Dec. 31, 2011 Hedge Funds [Member]
Pension and Other Postretirement Benefits Disclosure [Line Items]
Defined Benefit Plan, Target Allocation Percentage of Assets, Equity Securities				60.00%							75.00%
Defined Benefit Plan, Target Allocation Percentage of Assets, Debt Securities				30.00%
Defined Benefit Plan, Target Allocation Percentage of Assets, Other				10.00%							25.00%
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Redemption Restriction Flag													0
Net Periodic Benefit Cost, Expected Long-term Return on Assets				7.50%	7.50%			5.75%	5.75%		6.70%	6.90%
Actual Return on Plan Assets								6.27%	6.21%
Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year								8.50%	9.00%
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate								5.00%
Defined Benefit Plan, Effect of One Percentage Point Increase on Service and Interest Cost Components								$ 0.2
Defined Benefit Plan, Effect of One Percentage Point Decrease on Service and Interest Cost Components								(0.2)
Defined Benefit Plan, Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation								3.8
Defined Benefit Plan, Effect of One Percentage Point Decrease on Accumulated Postretirement Benefit Obligation								(3.0)
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Prior Service Cost (Credit), before Tax				(0.2)	0.3			4.9	7.5	4.4	(0.2)	(0.2)
Defined Benefit Plan, Gross Prescription Drug Subsidy Receipts Received								1.3	1.4
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year			45.9					2.6
Pension, Amount that will be recognized from AOCI to Income, after tax			29.9					1.7
Pension Contributions	100.0	67.0				2.9	3.2					5.0
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year				$ 53.0							$ 2.9