Significant Accounting Policies - Insurance Reserves and Derivatives (Details) - USD ($)	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017	Dec. 25, 2016
Derivative Financial Instruments
Other comprehensive income (loss), before tax	$ 4,254,000	$ 1,421,000	$ 1,492,000
Other comprehensive income (loss), net of tax	3,200,000	$ 900,000	$ 900,000
Minimum
Insurance Reserves
Employee insurance retention limit per occurrence	100,000
Maximum
Insurance Reserves
Employee insurance retention limit per occurrence	$ 1,000,000