Segment Information (Schedule Revenues By Geographic Area) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Number Of Reportable Segments			1
Revenues	$ 1,123,026	$ 921,210	$ 2,178,208	$ 1,764,931
Number of countries accounted for material revenues	0	0	0	0
United States [Member]
Revenues	550,659	450,327	1,035,633	849,877
International [Member]
Revenues	$ 572,367	$ 470,883	$ 1,142,575	$ 915,054