Property and Equipment Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 30, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,907,992	$ 2,658,566
Less accumulated depreciation and leasehold amortization	1,304,673	1,106,042
Total property and equipment, net	1,603,319	1,552,524
Computer and communications equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,511,445	1,363,799
Land, buildings and improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,051,658	961,550
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	216,586	226,471
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	123,945	102,151
Capital lease equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	3,197	3,197
Other equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,161	$ 1,398