Inventories - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Inventory Disclosure [Abstract]
Finished goods inventory step-up	$ 35.3	$ 284.4
Amounts charged for excess obsolete inventory	$ 195.4	$ 118.4	$ 51.8