Inventories (Tables)

3 Months Ended

Mar. 31, 2022

Inventory Disclosure [Abstract]

Inventories

The components of inventories and related changes in the allowance for excess and obsolete inventories account are as follows:

	March 31, 2022		December 31, 2021
	(in thousands)
Raw materials	$	140,424	$	124,480
Work in process	3,003		3,049
Finished goods	4,671		4,528
Total, gross	148,098		132,057
Less:  Allowance for excess and obsolete inventories	(2,007)		(1,787)
Total, net	$	146,091	$	130,270

Inventories (Allowance)

	Three Months Ended
	March 31, 2022		March 31, 2021
Allowance for excess and obsolete inventories:	(in thousands)
Balance, beginning of period	$	1,787	$	3,261
Provision for (recovery of) excess and	220		(194)
obsolete inventories
Inventories written off	—		(763)
Balance, end of period	$	2,007	$	2,304