Major Customers And Segment Information (Revenues Attributed By Geographical Region) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]
Operating Revenues	$ 327,861	$ 336,784	$ 315,563	$ 267,064	$ 362,368	$ 338,855	$ 309,225	$ 297,849	$ 1,247,272	$ 1,308,297	$ 1,032,497
UNITED STATES
Segment Reporting Information [Line Items]
Operating Revenues									845,056	823,693	517,120
Foreign Operation [Member]
Segment Reporting Information [Line Items]
Percentage of Operating Revenues									32.24765%	37.04082%	49.91559%
Middle East [Member]
Segment Reporting Information [Line Items]
Operating Revenues									51,930	49,941	46,724
Africa Primarily West Africa [Member]
Segment Reporting Information [Line Items]
Operating Revenues									79,991	75,484	75,497
Asia [Member]
Segment Reporting Information [Line Items]
Operating Revenues									26,203	21,039	15,973
Europe Primarily North Sea [Member]
Segment Reporting Information [Line Items]
Operating Revenues									101,834	107,766	79,210
Other Countries [Member]
Segment Reporting Information [Line Items]
Operating Revenues									0	388	437
Mexico Central And South America [Member]
Segment Reporting Information [Line Items]
Operating Revenues									$ 142,258	$ 229,986	$ 297,536