(14) Segment Data

The Company’s operations are classified into two reportable business segments as follows:

Marine Transportation — Marine transportation principally by United States flag vessels of liquid cargoes throughout the United States inland waterway system, along all three United States coasts, Alaska and Hawaii and, to a lesser extent, United States coastal transportation of dry-bulk cargoes. The principal products transported include petrochemicals, black oil, refined petroleum products and agricultural chemicals.

Diesel Engine Services — Provides after-market services for medium-speed and high-speed diesel engines, reduction gears and ancillary products for marine and power generation applications, and distributes and services high-speed diesel engines, transmissions, pumps and compression products, and manufactures and remanufactures oilfield service equipment, including pressure pumping units, for the land-based pressure pumping and oilfield service markets.

The Company’s two reportable business segments are managed separately based on fundamental differences in their operations. The Company’s accounting policies for the business segments are the same as those described in Note 1, Summary of Significant Accounting Policies. The Company evaluates the performance of its segments based on the contributions to operating income of the respective segments, and before income taxes, interest, gains or losses on disposition of assets, other nonoperating income, noncontrolling interests, accounting changes, and nonrecurring items. Intersegment sales for 2014, 2013 and 2012 were not significant.

The following table sets forth by reportable segment the revenues, profit or loss, total assets, depreciation and amortization, and capital expenditures attributable to the principal activities of the Company for the years ended December 31, 2014, 2013 and 2012 (in thousands):

	2014			2013			2012
Revenues:
Marine transportation	$	1,770,684		$	1,713,167		$	1,408,893
Diesel engine services		795,634			529,028			703,765
	$	2,566,318		$	2,242,195		$	2,112,658
Segment profit (loss):
Marine transportation	$	429,864		$	408,255		$	311,755
Diesel engine services		60,063			42,767			66,386
Other		(35,537	)		(42,344	)		(37,615	)
	$	454,390		$	408,678		$	340,526
Total assets:
Marine transportation	$	3,317,696		$	3,046,692		$	2,951,723
Diesel engine services		736,129			576,472			647,986
Other		88,084			59,353			53,419
	$	4,141,909		$	3,682,517		$	3,653,128
Depreciation and amortization:
Marine transportation	$	154,019		$	149,574		$	129,857
Diesel engine services		11,463			11,096			12,030
Other		3,830			3,767			3,260
	$	169,312		$	164,437		$	145,147
Capital expenditures:
Marine transportation	$	340,315		$	237,964		$	274,351
Diesel engine services		7,486			4,658			20,477
Other		7,343			10,605			17,339
	$	355,144		$	253,227		$	312,167

The following table presents the details of “Other” segment profit (loss) for the years ended December 31, 2014, 2013 and 2012 (in thousands):

	2014			2013			2012
General corporate expenses	$	(14,896	)	$	(15,728	)	$	(13,294	)
Interest expense		(21,461	)		(27,872	)		(24,385	)
Gain (loss) on disposition of assets		781			888			(14	)
Other income		39			368			78
	$	(35,537	)	$	(42,344	)	$	(37,615	)

The following table presents the details of “Other” total assets as of December 31, 2014, 2013 and 2012 (in thousands):

	2014		2013		2012
General corporate assets	$	85,545	$	57,197	$	51,611
Investment in affiliates		2,539		2,156		1,808
	$	88,084	$	59,353	$	53,419