Long-Term Debt (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011 Line of Credit	Sep. 21, 2011 Line of Credit	Dec. 31, 2011 $215 million term loan	Dec. 31, 2010 $215 million term loan	Dec. 31, 2011 $100 million Private Placement notes 5.64%, due in 2015	Dec. 31, 2010 $100 million Private Placement notes 5.64%, due in 2015	Dec. 31, 2011 $175 million Private Placement notes 3.89%, due in 2017	Dec. 31, 2010 $175 million Private Placement notes 3.89%, due in 2017	Dec. 31, 2011 $225 million Private Placement notes 4.47%, due in 2020	Dec. 31, 2010 $225 million Private Placement notes 4.47%, due in 2020	Dec. 31, 2011 Acquisition notes weighted average rate of 2.95% and weighted average maturity of 4.3 years	Dec. 31, 2011 Foreign bank debt weighted average rate 6.73% and Weighted average maturity of 2.2 years
Debt Instrument [Line Items]
Debt, maturity period											4 years 110 days	2 years 73 days
Weighted average interest rate %	1.73%										2.95%	6.73%
Maximum borrowing capacity of line of credit facility	$ 1,000.0	$ 850.0
Long-term debt, face amount			$ 215.0	$ 215.0	$ 100.0	$ 100.0	$ 175.0	$ 175.0	$ 225.0	$ 225.0
Interest rate %					5.64%		3.89%		4.47%