v2.4.0.6
Quarterly Financial Information (Amortization Of Stock-Based Compensation) (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended 12 Months Ended
Dec. 31, 2011
Sep. 30, 2011
Jun. 30, 2011
Mar. 31, 2011
Dec. 31, 2010
Sep. 30, 2010
Jun. 30, 2010
Mar. 31, 2010
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2009
Quarterly Financial Information [Line Items]                      
Allocated Share-based Compensation Expense                 $ 3,100 $ 3,800  
Cost Of Revenues [Member]
                     
Quarterly Financial Information [Line Items]                      
Allocated Share-based Compensation Expense 395 514 605 462 449 569 246 230 1,976 1,494 1,186
Selling And Marketing Expense [Member]
                     
Quarterly Financial Information [Line Items]                      
Allocated Share-based Compensation Expense 2,202 2,291 2,066 1,953 1,882 2,079 1,037 1,219 8,512 6,217 4,617
Research And Development Expense [Member]
                     
Quarterly Financial Information [Line Items]                      
Allocated Share-based Compensation Expense 394 536 627 431 590 699 315 264 1,988 1,868 1,111
General And Administrative Expense [Member]
                     
Quarterly Financial Information [Line Items]                      
Allocated Share-based Compensation Expense $ 1,829 $ 2,069 $ 2,208 $ 2,678 $ 2,938 $ 2,407 $ 1,889 $ 961 $ 8,784 $ 8,195 $ 2,942