. Business Segments

We aggregate our

five

current operating segments into

four

reporting segments

(Truckload, Dedicated, Intermodal and Brokerage) for financial reporting purposes.

The primary source of our operating revenue is provided by our Truckload segment through a combination of regional short-haul and medium-to-long-haul ful

l-load transportation services. We transport food and other consumer packaged goods that require a temperature-controlled or insulated environment, along with dry freight, across the United States and into and out of Mexico and Canada.

Our Dedicated segment provides cust

omized transportation solutions tailored to meet individual customers’ requirements, utilizing temperature-controlled trailers, dry vans and other specialized equipment within the United States. Our agreements with customers range from

three

five

years and are subject to annual rate reviews.

Our Intermodal segment transports our customers

’ freight within the United States primarily utilizing our temperature-controlled trailers and also, through

March 2015,

our dry containers on railroad flatcars for portions of trips, with the balance of the trips using our tractors or, to a lesser extent, contracted carriers.

Our Brokerage segment develops contractual relationships with and arranges for

third

-party carriers to transport freight for our customers in

temperature-controlled trailers and dry vans within the United States and into and out of Mexico through Marten Transport Logistics, LLC, which was established in

2007

and operates pursuant to brokerage authority granted by the DOT. We retain the billing, collection and customer management responsibilities.

The following table sets forth for the years indicated our operating revenue and operating income by segment. We do

not

prepare separate balance sheets by segment and, as a result, assets are

not

sepa

rately identifiable by segment.

(Dollars in thousands)	201 7		201 6		201 5
Operating revenue:
Truckload revenue, net of fuel surcharge revenue	$	336,596	$	339,967	$	348,101
Truckload fuel surcharge revenue		43,614		35,884		50,260
Total Truckload revenue		380,210		375,851		398,361

Dedicated revenue, net of fuel surcharge revenue		153,691		147,007		107,264
Dedicated fuel surcharge revenue		13,190		10,363		11,008
Total Dedicated revenue		166,881		157,370		118,272

Intermodal revenue, net of fuel surcharge revenue		70,282		64,508		65,877
Intermodal fuel surcharge revenue		10,339		6,982		11,081
Total Intermodal revenue		80,621		71,490		76,958

Brokerage revenue		70,408		66,433		71,403

Total operating revenue	$	698,120	$	671,144	$	664,994

Operating income:
Truckload	$	26,326	$	27,438	$	35,517
Dedicated		17,074		19,550		12,818
Intermodal		8,303		7,131		4,832
Brokerage		5,159		4,184		3,792
Total operating income before gain on disposition of facilities		56,862		58,303		56,959
Gain on disposition of facilities		-		-		4,104
Total operating income	$	56,862	$	58,303	$	61,063

Truckload segment depreciation expense was $

57.2

million,

$56.2

million and

$53.7

million, Dedicated segment depreciation expense was

$22.0

million,

$20.6

million and

$15.0

million, Intermodal segment depreciation expense was

$4.6

million,

$3.9

million and

$5.4

million, and Brokerage segment depreciation expense was

$1.3

million,

$1.7

million and

$1.3

million, in

2017,

2016

and

2015,

respectively.