Property, Plant, and Equipment, Net (Tables)

12 Months Ended

Dec. 31, 2018

Property, Plant and Equipment [Abstract]

Summary of Property, Plant, and Equipment

Depreciation expense is computed primarily using the straight-line method over the estimated useful lives of the assets, which are as follows:

Asset Classification	Estimated Useful Life
Buildings	30 years
Computer equipment	5 years
Furniture and fixtures	7 years
Leasehold improvements	Shorter of asset's useful life or remaining life of lease
Machinery and equipment	7 years
Vehicles	5 years

Property, plant, and equipment, net is comprised of the following (in thousands):

	December 31, 2018			December 31, 2017
Land	$	1,572		$	5,275
Buildings	233,185			227,864
Leasehold improvements	98,399			70,354
Machinery and equipment	334,351			260,637
Furniture and fixtures	10,779			18,415
Vehicles	1,506			1,517
Computer equipment	33,019			26,831
Construction-in-progress	40,771			32,235
Total property, plant, and equipment	753,582			643,128
Less: Accumulated depreciation	(209,436		)	(156,370		)
Property, plant, and equipment, net	$	544,146		$	486,758

Depreciation recognized by the Company is as follows (in thousands):

	Years Ended December 31,
	2018		2017		2016
Depreciation	$	64,417	$	41,962	$	29,314