Segment Information - Summary of segment's internal financial reports (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Segment Reporting Information [Line Items]
Contract revenues:	$ 888,616	$ 708,114	$ 1,700,232	$ 1,344,738
Income from operations:	32,438	26,245	59,864	51,147
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Income from operations:	(17,919)	(16,077)	(33,940)	(31,695)
T&D
Segment Reporting Information [Line Items]
Contract revenues:	503,737	415,235	949,060	780,091
T&D | Operating Segments
Segment Reporting Information [Line Items]
Income from operations:	37,734	32,810	70,554	63,240
C&I
Segment Reporting Information [Line Items]
Contract revenues:	384,879	292,879	751,172	564,647
C&I | Operating Segments
Segment Reporting Information [Line Items]
Income from operations:	$ 12,623	$ 9,512	$ 23,250	$ 19,602