(15) Segment Data

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

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

Distribution and Services — Provides after-market services and parts for engines, transmissions, reduction gears and related equipment used in oilfield service, marine, power generation, mining, on-highway, and other industrial applications. The Company also rents equipment including generators, fork lifts, pumps and compressors for use in a variety of industrial markets, and manufactures and remanufactures oilfield service equipment, including pressure pumping units, for the oilfield service and oil and gas operator and producer 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 revenues, based on market-based pricing, of the distribution and services segment from the marine transportation segment of $20,717,000, $24,672,000 and $26,203,000 in 2017, 2016 and 2015, respectively, as well as the related intersegment profit of $2,072,000, $2,467,000 and $2,620,000 in 2017, 2016 and 2015, respectively, have been eliminated from the tables below.

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, 2017, 2016 and 2015 (in thousands):

	2017			2016			2015
Revenues:
Marine transportation	$	1,324,106		$	1,471,893		$	1,663,090
Distribution and services		890,312			298,780			484,442
	$	2,214,418		$	1,770,673		$	2,147,532
Segment profit (loss):
Marine transportation	$	136,011		$	257,102		$	374,842
Distribution and services		86,585			3,186			18,921
Other		(149,582	)		(32,542	)		(32,051	)
	$	73,014		$	227,746		$	361,712
Total assets:
Marine transportation	$	3,485,099		$	3,613,951		$	3,444,785
Distribution and services		1,567,085			623,268			632,764
Other		75,243			52,676			63,009
	$	5,127,427		$	4,289,895		$	4,140,558
Depreciation and amortization:
Marine transportation	$	178,898		$	184,291		$	175,798
Distribution and services		20,387			12,833			12,498
Other		3,596			3,793			3,944
	$	202,881		$	200,917		$	192,240
Capital expenditures:
Marine transportation	$	165,421		$	217,423		$	311,862
Distribution and services		5,086			5,915			28,907
Other		6,715			7,728			4,706
	$	177,222		$	231,066		$	345,475

The following table presents the details of “Other” segment profit (loss) for the years ended December 31, 2017, 2016 and 2015 (in thousands):

	2017			2016			2015
General corporate expenses	$	(18,150	)	$	(14,966	)	$	(14,773	)
Interest expense		(21,472	)		(17,690	)		(18,738	)
Impairment of long-lived assets		(105,712	)		—			—
Gain (loss) on disposition of assets		(4,487	)		(127	)		1,672
Other income (expense)		239			241			(212	)
	$	(149,582	)	$	(32,542	)	$	(32,051	)

The following table presents the details of “Other” total assets as of December 31, 2017, 2016 and 2015 (in thousands):

	2017		2016		2015
General corporate assets	$	73,353	$	50,054	$	60,919
Investment in affiliates		1,890		2,622		2,090
	$	75,243	$	52,676	$	63,009