Property, Plant and Equipment

12 Months Ended

Dec. 31, 2017

Property, Plant and Equipment

Property, Plant and Equipment

Note 4: Property, Plant and Equipment

Property, plant and equipment are presented at cost net of accumulated depreciation and consist of the following:

December 31,	2017			2016
(in thousands)
Land	$	19,991		$	19,070
Buildings and leasehold improvements		138,072			142,741
Operating equipment		1,419,670			1,432,007
Computer software		23,017			22,050
Furniture and fixtures		7,656			8,056
Vehicles		494,833			469,570
Construction in progress		—			—
Gross property, plant and equipment		2,103,239			2,093,494
Less: accumulated depreciation		(1,659,311	)		(1,595,508	)
Net property, plant and equipment	$	443,928		$	497,986

Depreciation expense was $166.9 million in 2017, $220.6 million in 2016, and $274.4 million in 2015, and includes amounts recorded as costs of revenues. There were no capital leases outstanding as of December 31, 2017 and December 31, 2016. The Company had accounts payable for purchases of property and equipment of $7.1 million as of December 31, 2017, $3.4 million as of December 31, 2016, and $2.4 million as of December 31, 2015.