Property, Plant and Equipment - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Property, Plant and Equipment [Line Items]
Depreciation of property, plant and equipment	$ 40.8	$ 41.5	$ 79.8	$ 81.2