Segment Information (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($) segment	Jun. 30, 2021 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment			3
Revenues	$ 510,568	$ 401,666	$ 920,888	$ 716,982
Operating Income	41,090	32,720	69,359	55,475
Acquisition related costs	(230)	0	(485)	0
Operating Segments
Segment Reporting Information [Line Items]
Revenues	510,568	401,666	920,888	716,982
Operating Income	47,682	36,300	82,011	64,139
Corporate
Segment Reporting Information [Line Items]
Operating Income	(6,362)	(3,580)	(12,167)	(8,664)
E-Infrastructure Solutions Backlog \| Operating Segments
Segment Reporting Information [Line Items]
Revenues	233,548	123,743	402,475	220,315
Operating Income	32,824	24,714	54,109	42,526
Transportation Solutions Revenues \| Operating Segments
Segment Reporting Information [Line Items]
Revenues	191,381	203,153	351,880	350,207
Operating Income	5,107	4,796	8,793	7,462
Building Solutions Backlog - Commercial \| Operating Segments
Segment Reporting Information [Line Items]
Revenues	85,639	74,770	166,533	146,460
Operating Income	$ 9,751	$ 6,790	$ 19,109	$ 14,151

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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