Inventories

3 Months Ended

Mar. 31, 2021

Inventory Disclosure [Abstract]

Inventories

Inventories

Inventories are valued at the lower of cost or net realizable value. Cost is determined by the first-in, first-out (“FIFO”) method. We establish an allowance for excess and obsolete inventories based on product line changes, the feasibility of substituting parts and the need for supply and replacement parts.

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

	March 31, 2021		December 31, 2020
	(in thousands)
Raw materials	$	78,830	$	76,238
Work in process	2,577		2,088
Finished goods	4,937		7,154
Total, gross	86,344		85,480
Less:  Allowance for excess and obsolete inventories	(2,304)		(3,261)
Total, net	$	84,040	$	82,219

	Three Months Ended
	March 31, 2021		March 31, 2020
Allowance for excess and obsolete inventories:	(in thousands)
Balance, beginning of period	$	3,261	$	2,644
(Recoveries) provisions for excess and	(194)		(274)
obsolete inventories
Inventories written off	(763)		(5)
Balance, end of period	$	2,304	$	2,365