Property and Equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Components of Property, Plant and Equipment
Land	$ 6,896	$ 7,145
Buildings and leasehold improvements	34,290	34,351
Machinery, equipment and rental tools	62,775	85,611
Equipment in progress	15,963	12,304
Furniture and fixtures	2,635	2,749
Property and equipment	141,315	161,004
Less accumulated depreciation	(60,556)	(69,091)
Property and equipment, net	80,759	91,913
Transportation equipment [Member]
Components of Property, Plant and Equipment
Property and equipment	6,740	7,462
Computer equipment and software [Member]
Components of Property, Plant and Equipment
Property and equipment	$ 12,016	$ 11,382