Segment Information (Tables)

9 Months Ended

Sep. 30, 2025

Segment Reporting [Abstract]

Summary of information about reportable segments

The following tables present information about our reportable segments (in thousands):

	Mechanical Segment		Electrical Segment		Corporate		Consolidated
Total assets at September 30, 2025	$	3,689,895	$	1,184,210	$	903,746	$	5,777,851
Total assets at December 31, 2024	$	3,162,677	$	985,006	$	563,405	$	4,711,088

	Three Months Ended September 30, 2025
	Mechanical Segment		Electrical Segment		Corporate		Consolidated
Revenue	$	1,810,462	$	640,507	$	—	$	2,450,969
Cost of services		1,370,687		472,411		—		1,843,098
Gross profit		439,775		168,096		—		607,871
Selling, general and administrative expenses		152,442		60,021		17,116		229,579
Gain on sale of assets		(418)		(164)		—		(582)
Operating income (loss)	$	287,751	$	108,239	$	(17,116)	$	378,874
Amortization of identifiable intangible assets	$	14,001	$	5,525	$	—	$	19,526
Depreciation expense	$	13,048	$	2,600	$	400	$	16,048
Capital expenditures	$	28,881	$	5,787	$	664	$	35,332

	Three Months Ended September 30, 2024
	Mechanical Segment		Electrical Segment		Corporate		Consolidated
Revenue	$	1,438,617	$	373,749	$	—	$	1,812,366
Cost of services		1,146,245		284,407		—		1,430,652
Gross profit		292,372		89,342		—		381,714
Selling, general and administrative expenses		127,591		39,612		12,974		180,177
Gain on sale of assets		(675)		(672)		—		(1,347)
Operating income (loss)	$	165,456	$	50,402	$	(12,974)	$	202,884
Amortization of identifiable intangible assets	$	18,896	$	5,525	$	—	$	24,421
Depreciation expense	$	10,170	$	1,877	$	286	$	12,333
Capital expenditures	$	18,234	$	3,506	$	319	$	22,059
	Nine Months Ended September 30, 2025
	Mechanical Segment		Electrical Segment		Corporate		Consolidated
Revenue	$	4,851,349	$	1,604,225	$	—	$	6,455,574
Cost of services		3,732,449		1,201,941		—		4,934,390
Gross profit		1,118,900		402,284		—		1,521,184
Selling, general and administrative expenses		421,786		159,302		53,831		634,919
Gain on sale of assets		(1,141)		(439)		—		(1,580)
Operating income (loss)	$	698,255	$	243,421	$	(53,831)	$	887,845
Amortization of identifiable intangible assets	$	42,857	$	16,575	$	—	$	59,432
Depreciation expense	$	36,545	$	7,361	$	1,008	$	44,914
Capital expenditures	$	72,179	$	15,419	$	1,215	$	88,813
	Nine Months Ended September 30, 2024
	Mechanical Segment		Electrical Segment		Corporate		Consolidated
Revenue	$	4,075,305	$	1,084,367	$	—	$	5,159,672
Cost of services		3,286,249		830,750		—		4,116,999
Gross profit		789,056		253,617		—		1,042,673
Selling, general and administrative expenses		363,201		114,630		44,606		522,437
Gain on sale of assets		(1,605)		(1,173)		—		(2,778)
Operating income (loss)	$	427,460	$	140,160	$	(44,606)	$	523,014
Amortization of identifiable intangible assets	$	58,355	$	16,869	$	—	$	75,224
Depreciation expense	$	29,103	$	5,401	$	873	$	35,377
Capital expenditures	$	56,403	$	11,778	$	2,214	$	70,395