Annual report pursuant to Section 13 and 15(d)

Share-Based Compensation and Other Compensation Matters (Details 3)

v3.6.0.2
Share-Based Compensation and Other Compensation Matters (Details 3) - USD ($)
$ / shares in Units, $ in Thousands
12 Months Ended
Mar. 01, 2016
Mar. 05, 2015
Mar. 06, 2014
Mar. 01, 2013
Mar. 01, 2012
Mar. 03, 2011
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Performance share units [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                  
Grant date fair value (in dollars per share)             $ 38.21 $ 36.76 $ 35.09
Performance share units [Member] | 2011 PSU Grants [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                  
Stock awards granted (in shares or units)           56,883      
Aggregate grant date fair value           $ 2,796      
Unvested at the end of the period (in shares)             0    
Performance share units [Member] | 2012 PSU Grants [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                  
Stock awards granted (in shares or units)         54,070        
Aggregate grant date fair value         $ 1,772        
Unvested at the end of the period (in shares)             0    
Performance share units [Member] | 2013 PSU Grants [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                  
Stock awards granted (in shares or units)       69,579          
Aggregate grant date fair value       $ 1,867          
Unvested at the end of the period (in shares)             0    
Performance share units [Member] | 2014 PSU Grants [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                  
Stock awards granted (in shares or units)     49,103            
Aggregate grant date fair value     $ 1,723            
Unvested at the end of the period (in shares)             8,849    
Performance share units [Member] | 2015 PSU Grants [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                  
Stock awards granted (in shares or units)   45,656              
Aggregate grant date fair value   $ 1,678              
Unvested at the end of the period (in shares)             15,767    
Performance share units [Member] | 2016 PSU Grants [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                  
Stock awards granted (in shares or units) 26,299                
Aggregate grant date fair value $ 1,000                
Unvested at the end of the period (in shares)             24,850    
Deferred Share Award [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                  
Stock awards granted (in shares or units)             24,944 24,056  
Aggregate grant date fair value             $ 671 $ 642  
Grant date fair value (in dollars per share)             $ 26.89 $ 26.70