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Stock-Based Compensation - Valuation Assumptions for Stock Options (Detail) (Stock Options [Member])
3 Months Ended 9 Months Ended
Sep. 27, 2013
Sep. 28, 2012
Sep. 27, 2013
Sep. 28, 2012
Stock Options [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Expected term (years) 4 years 8 months 13 days 4 years 8 months 13 days 4 years 8 months 13 days 4 years 8 months 13 days
Volatility 46.00% 54.00% 51.00% 56.00%
Risk-free interest rate 1.50% 0.70% 0.80% 0.90%
Expected dividends 0.00% 0.00% 0.00% 0.00%