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Stockholders' Equity - Estimated Fair Value of ESPP Shares (Detail) - $ / shares
12 Months Ended
Dec. 26, 2015
Dec. 27, 2014
Dec. 28, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected life 6 months   6 months
Minimum [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Volatility 39.00% 46.00% 46.00%
Risk-free interest rate 0.13% 0.02% 0.10%
Expected life   3 months  
Estimated fair value, (in usd per share) $ 5.15 $ 2.05 $ 1.87
Maximum [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Volatility 53.00% 51.00% 49.00%
Risk-free interest rate 0.26% 0.11% 0.14%
Expected life   6 months  
Estimated fair value, (in usd per share) $ 6.43 $ 2.57 $ 3.00