Property, Plant and Equipment

12 Months Ended

Dec. 31, 2021

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

6. PROPERTY, PLANT AND EQUIPMENT

Property, plant and equipment consist of the following as of December 31 (in thousands):

	2021			2020
Machinery and equipment	$	471,667		$	312,870
Building and improvements		101,609			61,860
Forklifts and tractors		18,584			16,003
Computer equipment		15,022			11,948
Furniture and fixtures		2,283			1,534
Construction in process		87,700			157,465
Land		22,911			11,351
Total property, plant and equipment		719,776			573,031
Accumulated depreciation		(259,411	)		(236,494	)
Total property, plant and equipment, net	$	460,365		$	336,537

The Company had construction in process as of December 31, 2021 of approximately $87.7 million. The Company expects that substantially all of the above noted construction in process will be completed and put into service in the year ending December 31, 2022.

Depreciation expense for the years ended December 31, 2021, 2020, and 2019, totaled $35.5 million, $17.5 million, and $13.6 million, respectively.