Segment Information (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($) segment	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)
Segment Information
Number of reportable segments \| segment	2
Revenue	$ 700,131	$ 538,473
Gross Profit	117,093	106,665
Capital Expenditures	7,497	8,844
Total Assets	1,618,067		$ 1,505,012
Operating \| Mechanical Services Segment
Segment Information
Revenue	565,464	534,585
Gross Profit	108,922	105,852
Operating \| Electrical Services
Segment Information
Revenue	134,667	3,888
Gross Profit	$ 8,171	$ 813

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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