Summary of Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2018

Summary of Significant Accounting Policies

Schedule of disaggregation or revenue

	Three Months Ended June 30,								Six Months Ended June 30,
Revenue by Service Provided	2018				2017				2018				2017
HVAC and Plumbing	$	484,011	90	%	$	422,676	91	%	$	908,028	91	%	$	761,399	90	%
Building Automation Control Systems		26,261	5	%		27,925	6	%		46,306	5	%		50,760	6	%
Other		24,771	5	%		14,810	3	%		45,650	4	%		33,840	4	%
Total	$	535,043	100	%	$	465,411	100	%	$	999,984	100	%	$	845,999	100	%
	Three Months Ended June 30,								Six Months Ended June 30,
Revenue by Type of Customer	2018				2017				2018				2017
Industrial	$	114,077	21	%	$	97,756	21	%	$	214,177	21	%	$	185,370	22	%
Education		109,447	20	%		89,274	19	%		197,650	20	%		150,862	18	%
Office Buildings		79,309	15	%		76,470	16	%		148,429	15	%		128,904	15	%
Healthcare		71,930	13	%		59,322	13	%		135,113	14	%		111,089	13	%
Government		37,285	7	%		35,323	8	%		73,432	7	%		71,559	8	%
Retail, Restaurants and Entertainment		56,204	11	%		54,669	12	%		108,991	11	%		99,894	12	%
Multi-Family and Residential		36,040	7	%		30,260	7	%		69,092	7	%		57,130	7	%
Other		30,751	6	%		22,337	4	%		53,100	5	%		41,191	5	%
Total	$	535,043	100	%	$	465,411	100	%	$	999,984	100	%	$	845,999	100	%
	Three Months Ended June 30,								Six Months Ended June 30,
Revenue by Activity Type	2018				2017				2018				2017
New Construction	$	183,998	34	%	$	178,392	38	%	$	367,435	37	%	$	326,903	39	%
Existing Building Construction		207,775	39	%		146,980	32	%		362,972	36	%		265,246	31	%
Service Projects		51,586	10	%		46,428	10	%		91,761	9	%		89,037	11	%
Service Calls, Maintenance and Monitoring		91,684	17	%		93,611	20	%		177,816	18	%		164,813	19	%
Total	$	535,043	100	%	$	465,411	100	%	$	999,984	100	%	$	845,999	100	%

Schedule of contract assets and liabilities

The following table presents the changes in contract assets and contract liabilities (in thousands):

	Six Months Ended
	June 30, 2018
	Contract		Contract
	Assets		Liabilities
Balance at beginning of period	$	30,116	$	106,005
Change due to acquisitions		658		3,126
Change due to conditional versus unconditional		5,454		—
Reclassified to unbilled accounts receivable		(28,980)		—
Change in timing for performance obligation to be satisfied		—		24,831
Balance at June 30, 2018	$	7,248	$	133,962