Note 18—Reportable Segments

We segregate our business into five reportable segments: the Power segment, the Pipeline segment, the Utilities segment, the Transmission segment, which is a new reportable segment created in connection with the acquisition of Willbros, and the Civil segment. Each of our reportable segments is comprised of similar business units that specialize in services unique to the segment. Driving the end-user focused segments are differences in the economic characteristics of each segment, the nature of the services provided by each segment; the production processes of each segment; the type or class of customer using the segment’s services; the methods used by the segment to provide the services; and the regulatory environment of each segment’s customers.

The classification of revenue and gross profit for segment reporting purposes can at times require judgment on the part of management. Our segments may perform services across industries or perform joint services for customers in multiple industries. To determine reportable segment gross profit, certain allocations, including allocations of shared and indirect costs, such as facility costs, equipment costs and indirect operating expenses, were made.

The following is a brief description of the reportable segments:

The Power segment operates throughout the United States and in Canada and specializes in a range of services that include full EPC project delivery, turnkey construction, retrofits, upgrades, repairs, outages, and maintenance for entities in the petroleum, petrochemical, water, and other industries.

The Pipeline segment operates throughout the United States and specializes in a range of services, including pipeline construction, pipeline maintenance, pipeline facility work, compressor stations, pump stations, metering facilities, and other pipeline related services for entities in the petroleum and petrochemical industries.

The Utilities segment operates primarily in California, the Midwest, and the Southeast regions of the United States and specializes in a range of services, including utility line installation and maintenance, gas and electric distribution, streetlight construction, substation work, and fiber optic cable installation.

The Transmission segment operates primarily in the Southeastern and Gulf Coast regions of the United States and specializes in a range of services in electric and gas transmission and distribution, including comprehensive engineering, procurement, maintenance and construction, repair, and restoration of utility infrastructure.

The Civil segment operates primarily in the Southeastern and Gulf Coast regions of the United States and specializes in highway and bridge construction, airport runway and taxiway construction, demolition, heavy earthwork, soil stabilization, mass excavation, and drainage projects.

All intersegment revenue and gross profit, which were immaterial, have been eliminated in the following tables.

Segment Revenue

Revenue by segment for the three and nine months ended September 30, 2018 and 2017 were as follows (in thousands):


	For the three months ended September 30,
	2018			2017
			% of			% of
			Total			Total
Segment	Revenue		Revenue	Revenue		Revenue
Power	$	181,822	20.0%	$	154,178	25.3%
Pipeline		213,073	23.4%		84,357	13.9%
Utilities		269,652	29.7%		246,524	40.5%
Transmission		121,526	13.4%		—	0.0%
Civil		122,829	13.5%		123,252	20.3%
Total	$	908,902	100.0%	$	608,311	100.0%


	For the nine months ended September 30,
	2018			2017
			% of			% of
			Total			Total
Segment	Revenue		Revenue	Revenue		Revenue
Power	$	515,378	25.0%	$	443,191	24.6%
Pipeline		361,261	17.5%		402,425	22.4%
Utilities		665,214	32.3%		576,446	32.0%
Transmission (1)		163,980	7.9%		—	0.0%
Civil		355,975	17.3%		378,916	21.0%
Total	$	2,061,808	100.0%	$	1,800,978	100.0%

(1)

Represents results from the June 1, 2018 acquisition date of Willbros to September 30, 2018.

Segment Gross Profit

Gross profit by segment for the three and nine months ended September 30, 2018 and 2017 were as follows (in thousands):


	For the three months ended September 30,
	2018			2017
			% of			% of
			Segment			Segment
Segment	Gross Profit		Revenue	Gross Profit		Revenue
Power	$	32,077	17.6%	$	18,842	12.2%
Pipeline		24,999	11.7%		12,084	14.3%
Utilities		35,348	13.1%		36,081	14.6%
Transmission		13,958	11.5%		—	0.0%
Civil		123	0.1%		3,414	2.8%
Total	$	106,505	11.7%	$	70,421	11.6%


	For the nine months ended September 30,
	2018			2017
			% of			% of
			Segment			Segment
Segment	Gross Profit		Revenue	Gross Profit		Revenue
Power	$	76,674	14.9%	$	52,498	11.8%
Pipeline		43,568	12.1%		79,575	19.8%
Utilities		78,963	11.9%		76,701	13.3%
Transmission (1)		19,679	12.0%		—	0.0%
Civil		3,600	1.0%		1,183	0.3%
Total	$	222,484	10.8%	$	209,957	11.7%

(1)

Represents results from the June 1, 2018 acquisition date of Willbros to September 30, 2018.

Segment Goodwill

The amount of goodwill recorded by each segment at September 30, 2018 and at December 31, 2017 is presented in Note 7 – “Goodwill and Intangible Assets”.

Geographic Region — Revenue and Total Assets

The majority of our revenue is derived from customers in the United States with approximately 2.5% generated from sources outside of the United States, principally in Canada. At September 30, 2018 and December 31, 2017, approximately 3.0% of total assets were located outside of the United States.