Property And Equipment (Tables)

12 Months Ended

Dec. 31, 2017

Property Plant And Equipment [Abstract]

Schedule Of Property Plant And Equipment

		2017			2016
Land	$	9,992		$	9,992
Buildings and improvements		5,092			5,133
Furniture and fixtures		12,990			11,998
Operating equipment		805,748			788,989
Total property and equipment		833,822			816,112
Accumulated depreciation		(426,528	)		(403,104	)
Property and equipment — net	$	407,294		$	413,008