Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Effective tax rate, percentage	17.70%	17.70%	16.50%
Earnings of foreign entities	$ 12.3	$ 18.6	$ 20.0	$ 24.2
Unrecognized tax benefit for uncertain tax positions	24.3		24.3		$ 14.8
Accrued interest and penalties related to income tax liabilities	2.7		2.7		$ 2.4
Decrease in unrecognized tax benefits due to expiration of statutes of limitations and settlement of various audits	$ 3.9		$ 3.9