Annual report pursuant to Section 13 and 15(d)

Inventories - Narrative (Detail)

v3.8.0.1
Inventories - Narrative (Detail) - USD ($)
$ in Millions
Dec. 31, 2017
Dec. 31, 2016
Inventory Disclosure [Abstract]    
Reserve for inventory valuation $ 18.0 $ 15.4
Percentage of reserve for inventory valuation 10.70% 11.70%