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Stock-Based Compensation (Schedule of Valuation Assumptions) (Details)
3 Months Ended 9 Months Ended
Sep. 30, 2012
Oct. 02, 2011
Sep. 30, 2012
Oct. 02, 2011
Stock Options [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Expected term 4 years 11 months 1 day 4 years 11 months 5 days 5 years 6 months 29 days 4 years 11 months 5 days
Risk-free interest rate 0.67% 1.15% 0.89% 1.50%
Expected volatility 65.56% 60.93% 62.59% 59.96%
Expected dividend yield 0.00% 0.00% 0.00% 0.00%
Employee Stock Purchase Plan [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Expected term 6 months 1 day 6 months 6 months 1 day 6 months
Risk-free interest rate 0.14% 0.10% 0.14% 0.10%
Expected volatility 67.93% 47.00% 67.93% 47.00%
Expected dividend yield 0.00% 0.00% 0.00% 0.00%