v2.4.0.6
Employee Benefit Plans (Schedule Of Valuation Assumptions For Each Option Grant And Employee Stock Purchase Plan Purchase Rights) (Details)
12 Months Ended
Dec. 31, 2011
years
Dec. 31, 2010
years
Dec. 31, 2009
years
Stock Compensation Plan [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Dividend yield 0.00% 0.00% 0.00%
Expected life (in years) 1.0 1.0 1.0
Stock Options [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Dividend yield 0.00% 0.00% 0.00%
Expected life (in years) 6.1 6.1 6.1
Maximum [Member] | Stock Compensation Plan [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Risk free interest rate 0.26% 0.38% 1.00%
Expected volatility of the Company's stock 0.49% 0.45% 0.91%
Maximum [Member] | Stock Options [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Risk free interest rate 2.50% 2.80% 2.80%
Expected volatility of the Company's stock 0.69% 0.68% 0.67%
Minimum [Member] | Stock Compensation Plan [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Risk free interest rate 0.21% 0.35% 0.50%
Expected volatility of the Company's stock 0.31% 0.32% 0.69%
Minimum [Member] | Stock Options [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Risk free interest rate 1.50% 1.80% 2.00%
Expected volatility of the Company's stock 0.68% 0.67% 0.63%