Segment Information - Financial Data by Segment (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Sales to external customers	$ 35,775	$ 31,370
Operating income	2,010	1,534
Interest expense, net	315	501
Other expense (income), net	43	(2)
Consolidated income before income taxes	1,652	1,035
Assets	108,122		$ 110,749
United States Segment
Sales to external customers	30,444	27,439
Operating income	1,571	1,257
Assets	96,654		98,578
Canada Segment
Sales to external customers	2,421	1,413
Operating income	205	135
Assets	5,427		6,168
Europe Segment
Sales to external customers	2,910	2,518
Operating income	234	$ 142
Assets	$ 6,041		$ 6,003

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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