Business Segments - Reconciliation of Revenue from Segments to Consolidated (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Segment Reporting Information
Net Sales	$ 543,744	$ 497,497
Segment Operating Income	9,107	(7,206)
Segment Assets	312,401	365,310
Depreciation/Amortization	15,263	14,779
Expenditures for long-lived assets	4,513	7,633
Rail, Technologies, and Services
Segment Reporting Information
Net Sales	312,160	300,592
Infrastructure Solutions
Segment Reporting Information
Net Sales	231,584	196,905
Operating Segments
Segment Reporting Information
Net Sales	543,744	497,497
Segment Operating Income	20,928	2,322
Segment Assets	286,885	335,225
Depreciation/Amortization	13,434	13,284
Expenditures for long-lived assets	3,514	4,318
Operating Segments | Rail, Technologies, and Services
Segment Reporting Information
Net Sales	312,160	300,592
Segment Operating Income	12,306	11,454
Segment Assets	156,638	172,111
Depreciation/Amortization	5,172	5,620
Expenditures for long-lived assets	1,165	1,218
Operating Segments | Infrastructure Solutions
Segment Reporting Information
Net Sales	231,584	196,905
Segment Operating Income	8,622	(9,132)
Segment Assets	130,247	163,114
Depreciation/Amortization	8,262	7,664
Expenditures for long-lived assets	$ 2,349	$ 3,100