Property, Plant and Equipment and Leased Facilities and Equipment (Tables)

12 Months Ended

Dec. 31, 2020

Property Plant And Equipment [Abstract]

Summary of Property, Plant and Equipment

Property, plant and equipment consisted of the following at December 31, 2020 and 2019 (in thousands):

	Estimated		December 31,
	Useful Life		2020			2019
	(in Years)
Land		—	$	4,972		$	4,972
Buildings		25		36,581			35,580
Machinery and equipment	3 to 25			99,621			126,622
Furniture and fixtures	3 to 5			1,375			2,288
Transportation equipment	3 to 5			2,195			2,521
Improvements		15		38,934			40,377
Construction in progress		—		8,120			2,636
Total property, plant and equipment				191,798			214,996
Accumulated depreciation				(124,340	)		(144,512	)
Property, plant and equipment, net			$	67,458		$	70,484

Schedule of Minimum Rental Payments

Future minimum payments under leases having initial terms of more than twelve months are as follows (in thousands):

	Minimum Payments
2021	$	726
2022		737
2023		653
2024		564
2025		219
Total lease payments		2,899
Less: interest		(278	)
Present value of lease liabilities	$	2,621