Geographical Information (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
Revenue and long-lived assets by geographical segments        
Revenues $ 96,336 $ 67,852 $ 189,185 $ 131,362
United States
       
Revenue and long-lived assets by geographical segments        
Revenues 69,800 66,287 138,058 128,607
North America (Excluding U.S.)
       
Revenue and long-lived assets by geographical segments        
Revenues 5,817   12,103  
Europe, Middle East and Africa
       
Revenue and long-lived assets by geographical segments        
Revenues 13,604 1,126 26,907 2,045
Asia Pacific
       
Revenue and long-lived assets by geographical segments        
Revenues 5,495 175 9,798 337
Latin America
       
Revenue and long-lived assets by geographical segments        
Revenues $ 1,620 $ 264 $ 2,319 $ 373