Cost Of Revenue (Schedule Of Cost Of Revenue) (Details) (USD $) In Thousands | 3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2011 | Sep. 30, 2010 | Sep. 30, 2011 | Sep. 30, 2010 | |
| Cost Of Revenue [Line Items] | ||||
| Cost of revenue | $ 268,312 | $ 204,833 | $ 736,830 | $ 572,619 |
Personnel Expenses [Member] | ||||
| Cost Of Revenue [Line Items] | ||||
| Cost of revenue | 184,673 | 129,219 | 496,546 | 365,530 |
Operational Expenses [Member] | ||||
| Cost Of Revenue [Line Items] | ||||
| Cost of revenue | 70,605 | 62,068 | 200,693 | 167,897 |
Depreciation And Amortization [Member] | ||||
| Cost Of Revenue [Line Items] | ||||
| Cost of revenue | $ 13,034 | $ 13,546 | $ 39,591 | $ 39,192 |