Property, Plant and Equipment, net

12 Months Ended

Dec. 31, 2021

Property, Plant and Equipment [Abstract]

Property, plant and equipment consisted of the following:


	December 31,
(in thousands)	2021		2020
Land	$	28,175	$	28,553
Buildings and site improvements	202,393		203,421
Leasehold improvements	5,995		7,091
Machinery and equipment	399,079		372,923
	635,642		611,988
Less accumulated depreciation and amortization	(402,246)		(377,460)
	233,396		234,528
Capital projects in progress	26,473		20,656
	$	259,869	$	255,184

Property, plant and equipment as of December 31, 2021 and 2020, includes fully depreciated assets with an original cost of $234.0 million and $200.5 million, respectively, which are still in use in the Company’s operations. The Company capitalizes certain development costs associated with internal use software, including the direct costs of services provided by third-party consultants and payroll for internal employees, both of which are performing development and implementation activities on a software project. As of December 31, 2021 and 2020, the Company had capitalized software development costs net of accumulated amortization of $30.2 million and $29.4 million, respectively, included in Machinery and equipment and as of December 31, 2021 and 2020, $4.8 million and $5.5 million, respectively, was included in capital projects in progress.

Depreciation expense, including depreciation of equipment and amortization of internally developed software and software acquired through capital lease arrangements, was $36.1 million, $32.1 million and $32.6 million for the years ended December 31, 2021, 2020 and 2019, respectively.