Annual report pursuant to Section 13 and 15(d)

Fair Value Measurements (Details)

v3.8.0.1
Fair Value Measurements (Details) - Recurring - USD ($)
$ in Thousands
Dec. 31, 2017
Dec. 25, 2016
Assets:    
Investments in rabbi trust $ 9,292 $ 9,165
Total assets measured at fair value 9,292 9,165
Level 1    
Assets:    
Investments in rabbi trust 9,292 9,165
Total assets measured at fair value 9,292 9,165
Level 2    
Assets:    
Investments in rabbi trust 0 0
Total assets measured at fair value 0 0
Level 3    
Assets:    
Investments in rabbi trust 0 0
Total assets measured at fair value $ 0 $ 0