Property, Plant and Equipment (Tables)

12 Months Ended

Dec. 31, 2015

Property, Plant and Equipment

Schedule of property, plant and equipment at cost net of accumulated depreciation

December 31,	2015			2014
(in thousands)
Land	$	19,056		$	18,563
Buildings and leasehold improvements		142,715			134,994
Operating equipment		1,440,508			1,425,846
Computer software		19,650			19,005
Furniture and fixtures		8,043			7,835
Vehicles		480,899			479,628
Construction in progress		6			2,675
Gross property, plant and equipment		2,110,877			2,088,546
Less: accumulated depreciation		(1,422,542	)		(1,239,163	)
Net property, plant and equipment	$	688,335		$	849,383