Business Segments (Schedule of Total Assets for Reportable Segments) (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Segment Reporting Information [Line Items]
Total assets	$ 5,137,579	$ 5,160,422
Corporate and other
Segment Reporting Information [Line Items]
Total assets	(1,292,066)	(939,898)
Civil \| Operating Segments
Segment Reporting Information [Line Items]
Total assets	4,631,392	4,348,288
Building \| Operating Segments
Segment Reporting Information [Line Items]
Total assets	1,376,425	1,354,282
Specialty Contractors \| Operating Segments
Segment Reporting Information [Line Items]
Total assets	$ 421,828	$ 397,750

Amount of asset recognized for present right to economic benefit.

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+ Details