Operating Segment Information (Schedule Of Revenues By Geographic 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
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 480,346	$ 437,801	$ 410,951	$ 468,128	$ 491,604	$ 439,694	$ 411,644	$ 457,488	$ 1,797,226	$ 1,800,430	$ 1,583,064
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									1,399,528	1,412,881	1,284,407
Mexico [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									27,106	60,678	73,069
United Kingdom [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									361,014	308,464	211,915
Other Foreign Countries [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									$ 9,578	$ 18,407	$ 13,673