Inventories

3 Months Ended

Mar. 31, 2020

Inventory Disclosure [Abstract]

Inventories

4. Inventories

(table only in thousands)	March 31, 2020			December 31, 2019
Raw materials	$	14,865		$	15,218
Work in process		6,083			7,328
Finished goods		499			654
Obsolescence allowance		(2,839	)		(2,622	)
Total inventories	$	18,608		$	20,578

Amounts credited to the allowance for obsolete inventory and charged to cost of sales amounted to $0.1 million and $0.2 million for the three-month periods ended March 31, 2020 and 2019, respectively.