Segment Information (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) segment	Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Segment Information
Number of reportable segments \| segment			2
Revenue	$ 743,468	$ 650,302	$ 1,443,599	$ 1,188,775
Gross Profit	145,695	120,016	262,788	226,681
Capital Expenditures			14,539	15,680
Total Assets	1,675,443		1,675,443		$ 1,505,012
Operating \| Mechanical Services Segment
Segment Information
Revenue	622,700	553,031	1,188,164	1,087,616
Gross Profit	135,757	110,279	244,679	216,131
Operating \| Electrical Services
Segment Information
Revenue	120,768	97,271	255,435	101,159
Gross Profit	$ 9,938	$ 9,737	$ 18,109	$ 10,550

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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