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 of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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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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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services 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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Property, Plant and Equipment (Components of Property Plant and Equipment) (Details) - USD ($) $ in Millions	Jun. 30, 2019	Apr. 01, 2019	Mar. 31, 2019
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment		$ 41,709
Less accumulated depreciation	$ (20,420)	(20,512)	$ (20,539)
Property, plant and equipment, net	20,556	$ 21,197	21,201
Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment	107		246
Network equipment, site costs and related software [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment	25,110		24,967
Building and Building Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment	392		856
Non-network internal use software, office equipment, leased devices and other [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment	12,448		12,627
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Construction in progress	$ 2,919		$ 3,044