Note 7. Equity Incentive Plan and Stock-based Compensation (Details) - Shares Available for Grant
12 Months Ended
Dec. 28, 2014
Dec. 29, 2013
Dec. 30, 2012
Dec. 25, 2011
Employee Stock Option [Member] | Two Thousand Ten Equity Incentive Award Plan [Member]        
Note 7. Equity Incentive Plan and Stock-based Compensation (Details) - Shares Available for Grant [Line Items]        
Stock options granted/forfeited, net of forfeitures 300,123 (180,271) (2,478,327)  
Restricted Stock Units (RSUs) [Member] | Two Thousand Ten Equity Incentive Award Plan [Member]        
Note 7. Equity Incentive Plan and Stock-based Compensation (Details) - Shares Available for Grant [Line Items]        
Awards other than options granted, net of forfeitures/cancellations (1,444,520) (824,644) (1,028,600)  
Restricted Stock Units (RSUs) [Member]        
Note 7. Equity Incentive Plan and Stock-based Compensation (Details) - Shares Available for Grant [Line Items]        
Awards other than options granted, net of forfeitures/cancellations (1,568,509) (1,137,388) (1,328,143)  
Key Executive Rsu [Member] | Two Thousand Ten Equity Incentive Award Plan [Member]        
Note 7. Equity Incentive Plan and Stock-based Compensation (Details) - Shares Available for Grant [Line Items]        
Awards other than options granted, net of forfeitures/cancellations 357,870 36,836 (1,100,222)  
Key Executive Rsu [Member]        
Note 7. Equity Incentive Plan and Stock-based Compensation (Details) - Shares Available for Grant [Line Items]        
Awards other than options granted, net of forfeitures/cancellations     (1,100,222)  
Performance Stock Units [Member] | Two Thousand Ten Equity Incentive Award Plan [Member]        
Note 7. Equity Incentive Plan and Stock-based Compensation (Details) - Shares Available for Grant [Line Items]        
Awards other than options granted, net of forfeitures/cancellations (870,804) [1] (362,000)    
Performance Stock Units [Member]        
Note 7. Equity Incentive Plan and Stock-based Compensation (Details) - Shares Available for Grant [Line Items]        
Awards other than options granted, net of forfeitures/cancellations (888,804) (406,000)    
Two Thousand Ten Equity Incentive Award Plan [Member]        
Note 7. Equity Incentive Plan and Stock-based Compensation (Details) - Shares Available for Grant [Line Items]        
Shares available for grant under the 2010 Plan as of December 2,762,975 2,350,404 1,103,450 2,150,354
Annual increase under the 2010 Plan 2,069,902 2,577,033 3,560,245  
[1] Includes performance awards granted in fiscal 2014 at target. Additional awards that could be earned under the fiscal 2014 grant total 137,000.