Annual report pursuant to Section 13 and 15(d)

Stock Incentive Plans (Details)

v2.4.0.6
Stock Incentive Plans (Details) (USD $)
 12 Months Ended
Dec. 30, 2012
Dec. 25, 2011
Dec. 26, 2010
Share-based compensation plan disclosures      
Total stock-based compensation cost $ 3,800,000 $ 3,300,000 $ 4,100,000
Income tax benefits from stock-based compensation cost 1,500,000 1,300,000 1,700,000
Total unrecognized compensation cost 4,200,000    
Shares      
Outstanding, end of period (in shares) 705,000    
Exercisable as of the end of the period (in shares) 435,000    
Long-Term Cash Plan
      
Additional disclosure      
Performance and vesting period P3Y    
Compensation expense 1,500,000 400,000  
Stock Options
      
Share-based compensation plan disclosures      
Weighted average vesting period over which unrecognized compensation cost is expected to be recognized 1 year 2 months 12 days    
Shares      
Outstanding, beginning of period (in shares) 867,000    
Granted (in shares) 97,000    
Cancelled (in shares) (92,000)    
Exercised (in shares) (167,000)    
Outstanding, end of period (in shares) 705,000 867,000  
Vested and expected to vest, as of the end of the period (in shares) 660,000    
Exercisable as of the end of the period (in shares) 435,000    
Weighted Average Exercise Price      
Outstanding, beginning of period (in dollars per share) $ 25.14    
Granted (in dollars per share) $ 35.45    
Cancelled (in dollars per share) $ 31.83    
Exercised (in dollars per share) $ 18.19    
Outstanding, end of period (in dollars per share) $ 27.35 $ 25.14  
Vested and expected to vest, as of the end of the period (in dollars per share) $ 27.05    
Exercisable as of the end of the period (in dollars per share) $ 26.01    
Weighted Average Remaining Years of Contractual Life      
Outstanding, end of period 6 years 3 months 22 days    
Vested and expected to vest, as of the end of the period 6 years 2 months 1 day    
Exercisable as of the end of the period 5 years 3 months    
Aggregate Intrinsic Value      
Outstanding, end of period (in dollars) 5,424,000    
Vested and expected to vest, as of the end of the period (in dollars) 5,281,000    
Exercisable as of the end of the period (in dollars) 4,060,000    
Weighted average assumptions used in estimation of fair value of options      
Risk-free interest rate (as a percent) 0.70% 1.20% 1.50%
Expected years until exercise 4 years 1 month 6 days 3 years 7 months 6 days 3 years 7 months 6 days
Expected stock volatility (as a percent) 52.80% 60.30% 57.90%
Dividend yield (as a percent) 0.00% 0.00% 0.00%
Weighted average Black-Scholes fair value per share at date of grant (in dollars per share) $ 14.60 $ 14.21 $ 9.12
Total intrinsic value of options exercised (in dollars) $ 1,477,000 $ 657,000 $ 176,000
Restricted stock units
      
Share-based compensation plan disclosures      
Weighted average vesting period over which unrecognized compensation cost is expected to be recognized 1 year 2 months 12 days    
Restricted Stock
      
Share-based compensation plan disclosures      
Weighted average vesting period over which unrecognized compensation cost is expected to be recognized 2 months 12 days    
Performance-Based RSUs
      
Share-based compensation plan disclosures      
Weighted average vesting period over which unrecognized compensation cost is expected to be recognized 6 months    
2007 Stock Plan
      
Share-based compensation plan disclosures      
Maximum number of shares of the company's common stock that may be issued or transferred 2,074,600    
Period following the change in control during which termination of an individual without cause will trigger vesting of award 2 years    
Expiration term 10 years    
Vested (in shares) 308,279    
Shares      
Outstanding, end of period (in shares) 578,430    
2007 Stock Plan | Restricted Stock
      
Shares      
Outstanding, beginning of period (in shares) 14,000    
Cancelled (in shares) (1,000)    
Vested (in shares) (9,000)    
Outstanding, end of period (in shares) 4,000    
Weighted Average Grant-Date Fair Value (per share)      
Outstanding, beginning of period (in dollars per share) $ 20.85    
Cancelled (in dollars per share) $ 14.93    
Vested (in dollars per share) $ 23.73    
Outstanding, end of period (in dollars per share) $ 14.93    
2007 Stock Plan | Restricted Stock | Directors
      
Share-based compensation plan disclosures      
Vesting period 3 years    
2007 Stock Plan | Restricted Stock | Executive officers and other key employees
      
Share-based compensation plan disclosures      
Vesting period 4 years    
2007 Stock Plan | Time Based RSUs
      
Share-based compensation plan disclosures      
Vesting period 4 years    
Shares      
Outstanding, beginning of period (in shares) 165,000    
Granted (in shares) 66,000    
Cancelled (in shares) (6,000)    
Vested (in shares) (45,000)    
Outstanding, end of period (in shares) 180,000    
Weighted Average Grant-Date Fair Value (per share)      
Outstanding, beginning of period (in dollars per share) $ 24.85    
Granted (in dollars per share) $ 33.67    
Cancelled (in dollars per share) $ 24.81    
Vested (in dollars per share) $ 24.83    
Outstanding, end of period (in dollars per share) $ 28.52    
2007 Stock Plan | Performance-Based RSUs
      
Shares      
Outstanding, beginning of period (in shares) 37,000    
Cancelled (in shares) (2,000)    
Outstanding, end of period (in shares) 35,000    
Additional disclosure      
Number of shares of common stock per award upon conversion 1    
Performance period 3 years    
Other stock-based compensation plans
      
Share-based compensation plan disclosures      
Expiration term 10 years    
Number of stock-based compensation plans 4    
Shares      
Outstanding, end of period (in shares) 126,514    
Other stock-based compensation plans | Minimum
      
Share-based compensation plan disclosures      
Vesting period 1 year    
Other stock-based compensation plans | Maximum
      
Share-based compensation plan disclosures      
Vesting period 4 years