Goodwill and Other Intangible Assets - Schedule of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Goodwill
Goodwill, beginning balance	$ 20,340	$ 19,565
Acquisitions		450
Acquisitions	(22)
Foreign currency translation impact	(166)	325
Goodwill, ending balance	20,152	20,340
Rail, Technologies, and Services
Goodwill
Goodwill, beginning balance	14,743	14,418
Acquisitions		0
Acquisitions	0
Foreign currency translation impact	(166)	325
Goodwill, ending balance	14,577	14,743
Precast Concrete Products
Goodwill
Goodwill, beginning balance	2,586	2,136
Acquisitions		450
Acquisitions	(22)
Foreign currency translation impact	0	0
Goodwill, ending balance	2,564	2,586
Steel Products and Measurement
Goodwill
Goodwill, beginning balance	3,011	3,011
Acquisitions		0
Acquisitions	0
Foreign currency translation impact	0	0
Goodwill, ending balance	$ 3,011	$ 3,011

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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