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Stockholders' Equity - Employee Stock Purchase Plan (Details) - $ / shares
12 Months Ended
Dec. 27, 2015
Dec. 28, 2014
Dec. 29, 2013
Mar. 28, 2014
Mar. 27, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Number of shares available for future issuance       1,550,000 2,306,256
Number of shares issued under the plan 946,000        
Employee Stock Purchase Plan          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Number of shares authorized 5,200,000        
Minimum weekly employment threshold to qualify for ESPP 20 hours        
Minimum annual employment threshold to qualify for ESPP 5 months        
Maximum percentage of employee compensation eligible to purchase shares under ESPP 15.00%        
Purchase price of common stock as a percent of fair market value 85.00%        
Cumulative number of shares issued under ESPP 3,400,000        
Number of shares available for future issuance 1,800,000        
Average share price of shares issued under the plan $ 4.25        
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]          
Expected term (in years) 6 months 6 months 6 months    
Risk-free interest rate, lower range 0.11% 0.07% 0.10%    
Risk-free interest rate, upper range 0.12% 0.10% 0.11%    
Expected volatility, lower range 39.63% 40.14% 36.95%    
Expected volatility, upper range 40.91% 40.23% 43.70%    
Expected dividend yield 0.00% 0.00% 0.00%    
Weighted average grant-date fair value per share (in dollars per share) $ 1.43 $ 2.09 $ 1.50