Property and Equipment Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 28, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 3,699,224	$ 3,578,317
Less accumulated depreciation and leasehold amortization	1,895,141	1,719,545
Total property and equipment, net	1,804,083	1,858,772
Computer and communications equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,939,517	1,855,550
Land, buildings and improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,403,835	1,374,541
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	208,496	214,608
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	146,351	132,540
Other equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,025	$ 1,078

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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