Inventories (Tables)

12 Months Ended

Dec. 31, 2021

Inventory Disclosure [Abstract]

Summary of Inventories

Inventories as of December 31, 2021 and 2020 consist of the following (in thousands):

	December 31,
	2021			2020
Finished goods	$	9,594		$	6,425
Semi-finished goods and work-in-process		25,968			30,968
Raw materials		9,443			6,526
Materials in-transit		95			1,021
Less: inventory reserve		(5,730	)		(5,901	)
Inventories, net	$	39,370		$	39,039

Changes in Inventory Reserve

Changes in inventory reserve for the years ended December 31, 2021, 2020 and 2019 are as follows (in thousands):

	Year Ended December 31,
	2021			2020			2019
Beginning balance	$	(5,901	)	$	(5,947	)	$	(4,845	)
Change in reserve
Inventory reserve charged to costs of sales		(7,626	)		(7,268	)		(12,941	)
Sale of previously reserved inventory		5,349			4,349			2,938
		(2,277	)		(2,919	)		(10,003	)
Write off		1,875			2,679			8,451
Translation adjustments		573			(408	)		450
Reclassified to assets held for sale		—			694			—
Ending balance	$	(5,730	)	$	(5,901	)	$	(5,947	)