Geographical Information (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended
Mar. 31, 2012
Mar. 31, 2011
Revenue and long-lived assets by geographical segments    
Revenues $ 92,849 $ 63,510
United States
   
Revenue and long-lived assets by geographical segments    
Revenues 68,258 62,320
North America (Excluding U.S.)
   
Revenue and long-lived assets by geographical segments    
Revenues 6,286  
Europe, Middle East and Africa
   
Revenue and long-lived assets by geographical segments    
Revenues 13,303 919
Asia Pacific
   
Revenue and long-lived assets by geographical segments    
Revenues 4,303 162
Latin America
   
Revenue and long-lived assets by geographical segments    
Revenues $ 699 $ 109