Goodwill and Other Intangible Assets - Schedule of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Goodwill
Goodwill, beginning balance	$ 19,565	$ 19,258
Foreign currency translation impact	325	307
Acquisitions	450
Goodwill, ending balance	20,340	19,565
Rail Technologies and Services
Goodwill
Goodwill, beginning balance	14,418	14,111
Foreign currency translation impact	325	307
Acquisitions	0
Goodwill, ending balance	14,743	14,418
Infrastructure Solutions
Goodwill
Goodwill, beginning balance	5,147	5,147
Foreign currency translation impact	0	0
Acquisitions	450
Goodwill, ending balance	$ 5,597	$ 5,147

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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