Summary of Significant Accounting Policies - Estimated Useful Lives of Property Plant and Equipment (Detail)	12 Months Ended
	Dec. 31, 2017
Buildings [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment estimated useful life	40 years
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment estimated useful life	10 years
Forklifts and Tractors [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment estimated useful life	5 years
Computer Equipment and Software [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment estimated useful life	5 years
Minimum [Member] | Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment estimated useful life	3 years
Maximum [Member] | Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment estimated useful life	11 years