Business Segments - Reconciliation of Revenue from Segments to Consolidated (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Segment Reporting Information
Net Sales	$ 115,488	$ 98,794
Segment Operating Profit (Loss)	503	(2,287)
Operating Segments
Segment Reporting Information
Net Sales	115,488	98,794
Segment Operating Profit (Loss)	2,032	(1,900)
Rail, Technologies, and Services
Segment Reporting Information
Net Sales	64,384	63,710
Rail, Technologies, and Services | Operating Segments
Segment Reporting Information
Net Sales	64,384	63,710
Segment Operating Profit (Loss)	2,388	1,039
Precast Concrete Products
Segment Reporting Information
Net Sales	24,288	15,010
Precast Concrete Products | Operating Segments
Segment Reporting Information
Net Sales	24,288	15,010
Segment Operating Profit (Loss)	(348)	(791)
Steel Products and Measurement
Segment Reporting Information
Net Sales	26,816	20,074
Steel Products and Measurement | Operating Segments
Segment Reporting Information
Net Sales	26,816	20,074
Segment Operating Profit (Loss)	$ (8)	$ (2,148)