Annual report pursuant to Section 13 and 15(d)

Stock Incentive Plans (Details)

v3.20.4
Stock Incentive Plans (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 27, 2020
Dec. 29, 2019
Dec. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized 275,000 660,000  
Total stock-based compensation cost $ 4.3 $ 3.3 $ 4.0
Income tax benefits from stock-based compensation cost 0.3 $ 0.3 $ 0.5
Total unrecognized compensation cost $ 8.2    
Stock Options      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Shares outstanding 470,000 288,000  
Weighted average remaining vesting period 1 year 2 months 8 days    
Restricted Stock Units (RSUs) [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Weighted average remaining vesting period 1 year 1 month 13 days    
Performance Shares      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Weighted average remaining vesting period 1 year 9 months 25 days    
2017 Stock Plan      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Maximum number of shares of the company's common stock that may be issued or transferred (in shares) 1,565,182   630,182
2017 Stock Plan | Performance Shares      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting period 3 years 3 years  
2017 and 2007 Performance Incentive Plans      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
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    
2017 and 2007 Performance Incentive Plans | Restricted Stock Units (RSUs) [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting period 4 years    
2007 Performance Incentive Plan [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Shares outstanding 219,874    
Minimum | 2017 and 2007 Performance Incentive Plans      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting period 1 year    
Maximum | 2017 and 2007 Performance Incentive Plans      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting period 4 years