Fair Value of Financial Instruments - Additional Information (Detail) (USD $) In Millions, unless otherwise specified						12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012 Other Accounts Receivable	Dec. 31, 2012 Accrued Expenses	Dec. 31, 2011 Accrued Expenses	Dec. 31, 2012 Other income (expenses), net	Dec. 31, 2011 Other income (expenses), net	Dec. 31, 2010 Other income (expenses), net	Dec. 31, 2012 Other, net	Dec. 31, 2011 Other, net	Dec. 31, 2010 Other, net	Dec. 31, 2012 4.50% Senior Notes	Dec. 31, 2011 4.50% Senior Notes	Dec. 31, 2010 4.50% Senior Notes	Dec. 31, 2012 5.10% Senior Notes	Dec. 31, 2011 5.10% Senior Notes	Jan. 20, 2005 5.10% Senior Notes
Fair Value, Option, Quantitative Disclosures [Line Items]
Debt instrument, interest rate												4.50%	4.50%	4.50%	5.10%	5.10%	5.10%
Foreign currency forward contracts, notional values	$ 274.0	$ 148.7
Fair value of foreign currency forward contracts, assets			0.3
Fair value of foreign currency forward contracts, liabilities				0.8	0.9
Recognized gains (losses) of foreign currency forward contracts						5.1	1.0	(6.5)
Change in the fair value of foreign currency forward contracts									(5.1)	(1.0)	6.5
Cash settlements									$ 4.8	$ (3.0)	$ (1.3)