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Revenue - Schedule of Sales by Major Product Line (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Disaggregation of Revenue
Total net sales	$ 138,286	$ 137,466	$ 379,636	$ 402,582
Rail, Technologies, and Services
Disaggregation of Revenue
Total net sales	77,788	79,498	207,776	247,715
Precast Concrete Products
Disaggregation of Revenue
Total net sales	43,272	42,688	117,650	97,730
Steel Products
Disaggregation of Revenue
Total net sales	17,226	15,280	54,210	57,137
Infrastructure Solutions
Disaggregation of Revenue
Total net sales	60,498	57,968	171,860	154,867
Rail Products | Rail, Technologies, and Services
Disaggregation of Revenue
Total net sales	44,628	47,442	121,517	156,803
Global Friction Management | Rail, Technologies, and Services
Disaggregation of Revenue
Total net sales	21,313	19,548	57,307	51,008
Technology Services and Solutions | Rail, Technologies, and Services
Disaggregation of Revenue
Total net sales	$ 11,847	$ 12,508	$ 28,952	$ 39,904

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