Segment and Geographic Information Narrative (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013 countries customers	Jun. 30, 2012 countries customers	Jun. 30, 2013 countries customers	Jun. 30, 2012 customers countries	Dec. 31, 2012
Segment Reporting Information [Line Items]
Property and equipment, net	$ 405,653		$ 405,653		$ 345,091
Number of foreign countries greater than 10% revenue	0	0	0	0
Number of customers accounted for 10% or more of total revenues	0	0	0	0
United States
Segment Reporting Information [Line Items]
Property and equipment, net	264,300		264,300		225,500
Outside the United States [Member]
Segment Reporting Information [Line Items]
Property and equipment, net	$ 141,400		$ 141,400		$ 119,600