Difference Between Income Tax Expense and Amount Computed by Applying Statutory United States Federal Income Tax Rate to Pre-Tax Earnings (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Taxes [Line Items]
Statutory federal income tax expense	$ 177.4	$ 116.7	$ 113.0
U.S. state income taxes	9.7	5.9	6.0
Foreign tax rate differential	(36.2)	(36.0)	(27.8)
Non-deductible charges/losses and other	4.2	14.8	8.0
Research and development credit	(13.9)	(1.6)	(4.0)
Total income tax expense	$ 141.2	$ 99.8	$ 95.2