Valuation and Qualifying Accounts Valuation and Qualifying Accounts (Details) - USD ($)	12 Months Ended
	Dec. 27, 2016	Dec. 29, 2015	Dec. 30, 2014
Self Insurance Reserve [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Valuation Allowances and Reserves, Balance	$ 37,208,000	$ 32,559,000	$ 31,545,000
Valuation Allowances and Reserves, Charged to Cost and Expense	49,241,000	54,341,000	50,729,000
Valuation Allowances and Reserves, Deductions	(44,729,000)	(49,692,000)	(49,715,000)
Valuation Allowances and Reserves, Balance	41,720,000	37,208,000	32,559,000
Valuation Allowance of Deferred Tax Assets [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Valuation Allowances and Reserves, Balance	5,299,000	4,625,000	3,173,000
Valuation Allowances and Reserves, Charged to Cost and Expense	13,814,000	674,000	1,452,000
Valuation Allowances and Reserves, Deductions	(7,787,000)	0	0
Valuation Allowances and Reserves, Balance	$ 11,326,000	$ 5,299,000	$ 4,625,000