Leases (Details) $ in Thousands	12 Months Ended
	Dec. 27, 2017 USD ($)
Operating Leased Assets [Line Items]
Term of typical renewal options on land and building leases	5 years
Capital Lease Commitments:
2018	$ 8,863
2019	8,429
2020	7,796
2021	7,142
2022	6,483
Thereafter	33,073
Total	71,786
Less imputed interest	41,564
Present value of capital lease obligations	30,222
Operating Lease Commitments:
2018	26,214
2019	23,152
2020	19,403
2021	16,510
2022	13,787
Thereafter	54,067
Total	153,133
Operating Lease Receipts:
2018	23,681
2019	21,029
2020	18,355
2021	16,394
2022	14,669
Thereafter	67,606
Total	$ 161,734
Minimum [Member]
Operating Leased Assets [Line Items]
Initial terms of land and building leases	10 years
Maximum [Member]
Operating Leased Assets [Line Items]
Initial terms of land and building leases	15 years