Revenue from Contracts with Customers (Tables)

12 Months Ended

Dec. 31, 2022

Revenue from Contracts with Customers

Schedule of contracts in progress

Contracts in progress are as follows (in thousands):

	December 31,
	2022		2021
Costs incurred on contracts in progress	$	4,801,264	$	3,723,715
Estimated earnings, net of losses		796,260		589,286
Less—Billings to date		(5,953,973)		(4,527,801)
Less—Unbilled accounts receivable		(77,030)		(61,881)
Less—Unbilled accounts receivable credit allowance		(1,011)		(715)
	$	(434,490)	$	(277,396)
Costs and estimated earnings in excess of billings	$	27,211	$	29,900
Plus—Costs and estimated earnings in excess of billings credit allowance		80		84
Billings in excess of costs and estimated earnings		(461,781)		(307,380)
	$	(434,490)	$	(277,396)

Schedule of disaggregation of revenue

Our consolidated 2022 revenue was derived from contracts to provide service activities in the mechanical and electrical services segments we serve. Refer to Note 16 “Segment Information” for additional information on our reportable segments. We disaggregate our revenue from contracts with customers by activity, customer type and service provided, as we believe it best depicts how the nature, amount, timing and uncertainty of our revenue and cash flows are affected by economic factors. See details in the following tables (dollars in thousands):

	Year Ended December 31,
Revenue by Service Provided	2022				2021				2020
Mechanical Services	$	3,178,475	76.8	%	$	2,542,623	82.7	%	$	2,430,632	85.1	%
Electrical Services		961,889	23.2	%		531,013	17.3	%		426,027	14.9	%
Total	$	4,140,364	100.0	%	$	3,073,636	100.0	%	$	2,856,659	100.0	%
	Year Ended December 31,
Revenue by Type of Customer	2022				2021				2020
Industrial	$	1,973,252	47.7	%	$	1,356,688	44.1	%	$	1,112,075	38.9	%
Healthcare		584,023	14.1	%		417,901	13.6	%		371,105	13.0	%
Education		445,638	10.8	%		390,251	12.7	%		487,922	17.1	%
Office Buildings		349,235	8.4	%		308,799	10.1	%		319,426	11.2	%
Retail, Restaurants and Entertainment		311,697	7.5	%		213,386	6.9	%		239,541	8.4	%
Government		255,314	6.2	%		174,813	5.7	%		163,717	5.7	%
Multi-Family and Residential		126,339	3.0	%		112,779	3.7	%		86,799	3.0	%
Other		94,866	2.3	%		99,019	3.2	%		76,074	2.7	%
Total	$	4,140,364	100.0	%	$	3,073,636	100.0	%	$	2,856,659	100.0	%

	Year Ended December 31,
Revenue by Activity Type	2022				2021				2020
New Construction	$	2,011,992	48.6	%	$	1,421,784	46.3	%	$	1,333,739	46.7	%
Existing Building Construction		1,210,512	29.2	%		963,461	31.3	%		910,807	31.9	%
Service Projects		382,155	9.2	%		278,582	9.1	%		241,402	8.4	%
Service Calls, Maintenance and Monitoring		535,705	13.0	%		409,809	13.3	%		370,711	13.0	%
Total	$	4,140,364	100.0	%	$	3,073,636	100.0	%	$	2,856,659	100.0	%

Schedule of contract assets and liabilities

	Year Ended December 31,					Year Ended December 31,
	2022				2021
	Contract		Contract		Contract		Contract
	Assets		Liabilities		Assets		Liabilities
Balance at beginning of period	$	29,900	$	307,380	$	18,622	$	226,237
Change due to acquisitions / disposals		2,426		1,160		10,356		36,523
Change related to credit allowance		4		—		(5)		—
Other changes in the period		(5,119)		239,753		927		44,620
Balance at end of period	$	27,211	$	548,293	$	29,900	$	307,380