Retirement Plans (Details) $ in Millions	12 Months Ended
	Dec. 27, 2016 USD ($) item	Dec. 29, 2015 USD ($)	Dec. 30, 2014 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Number of retirement benefit plans | item	2
Expenses related to the Plans | $	$ 1.3	$ 2.2	$ 1.7
401(k) Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Employees contribution of annual salaries	15.00%
Deferred-Compensation Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Employees contribution of annual salaries	80.00%