Revenue from Contracts with Customers - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Disaggregation of Revenue
Revenue	$ 3,766,302	$ 2,450,969	$ 9,897,290	$ 6,455,574
Percentage of revenue from contract with customer (as a percent)	100.00%	100.00%	100.00%	100.00%
New construction
Disaggregation of Revenue
Revenue	$ 2,868,291	$ 1,597,452	$ 7,455,849	$ 3,919,402
Percentage of revenue from contract with customer (as a percent)	76.20%	65.20%	75.30%	60.70%
Existing building construction
Disaggregation of Revenue
Revenue	$ 528,261	$ 527,139	$ 1,448,331	$ 1,626,978
Percentage of revenue from contract with customer (as a percent)	14.00%	21.50%	14.60%	25.20%
Service projects
Disaggregation of Revenue
Revenue	$ 190,592	$ 150,383	$ 473,422	$ 415,868
Percentage of revenue from contract with customer (as a percent)	5.10%	6.10%	4.80%	6.50%
Service calls, maintenance, and monitoring
Disaggregation of Revenue
Revenue	$ 179,158	$ 175,995	$ 519,688	$ 493,326
Percentage of revenue from contract with customer (as a percent)	4.70%	7.20%	5.30%	7.60%
Technology
Disaggregation of Revenue
Revenue	$ 2,290,001	$ 1,122,528	$ 5,823,870	$ 2,734,280
Percentage of revenue from contract with customer (as a percent)	60.80%	45.80%	58.80%	42.40%
Manufacturing
Disaggregation of Revenue
Revenue	$ 631,631	$ 543,110	$ 1,703,430	$ 1,468,936
Percentage of revenue from contract with customer (as a percent)	16.80%	22.20%	17.20%	22.70%
Healthcare
Disaggregation of Revenue
Revenue	$ 236,387	$ 206,965	$ 687,704	$ 589,848
Percentage of revenue from contract with customer (as a percent)	6.30%	8.50%	6.90%	9.10%
Education
Disaggregation of Revenue
Revenue	$ 178,515	$ 171,707	$ 480,184	$ 527,794
Percentage of revenue from contract with customer (as a percent)	4.60%	7.00%	4.90%	8.20%
Government
Disaggregation of Revenue
Revenue	$ 139,255	$ 122,284	$ 415,075	$ 326,318
Percentage of revenue from contract with customer (as a percent)	3.70%	5.00%	4.20%	5.10%
Office buildings
Disaggregation of Revenue
Revenue	$ 100,033	$ 125,458	$ 272,841	$ 358,445
Percentage of revenue from contract with customer (as a percent)	2.70%	5.10%	2.80%	5.50%
Retail, restaurants, and entertainment
Disaggregation of Revenue
Revenue	$ 99,942	$ 88,503	$ 271,121	$ 250,619
Percentage of revenue from contract with customer (as a percent)	2.70%	3.60%	2.70%	3.90%
Multi-family and residential
Disaggregation of Revenue
Revenue	$ 44,821	$ 35,342	$ 124,534	$ 96,909
Percentage of revenue from contract with customer (as a percent)	1.20%	1.40%	1.30%	1.50%
Other
Disaggregation of Revenue
Revenue	$ 45,717	$ 35,072	$ 118,531	$ 102,425
Percentage of revenue from contract with customer (as a percent)	1.20%	1.40%	1.20%	1.60%
Mechanical segment
Disaggregation of Revenue
Revenue	$ 2,582,889	$ 1,810,462	$ 6,940,178	$ 4,851,349
Percentage of revenue from contract with customer (as a percent)	68.60%	73.90%	70.10%	75.10%
Electrical segment
Disaggregation of Revenue
Revenue	$ 1,183,413	$ 640,507	$ 2,957,112	$ 1,604,225
Percentage of revenue from contract with customer (as a percent)	31.40%	26.10%	29.90%	24.90%