Goodwill and Other Intangible Assets - Schedule of Goodwill (Details) $ in Thousands	9 Months Ended
Sep. 30, 2021 USD ($)
Goodwill
Goodwill, beginning balance	$ 20,340
Larken purchase price adjustment	(21)
Foreign currency translation impact	(172)
Goodwill, ending balance	20,147
Rail Technologies and Services
Goodwill
Goodwill, beginning balance	14,743
Larken purchase price adjustment	0
Foreign currency translation impact	(172)
Goodwill, ending balance	14,571
Infrastructure Solutions
Goodwill
Goodwill, beginning balance	5,597
Larken purchase price adjustment	(21)
Foreign currency translation impact	0
Goodwill, ending balance	$ 5,576

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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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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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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