Supplemental Financial Statement Information (Property and Equipment) (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Property, Plant and Equipment, Net [Abstract]
Property and equipment, gross	$ 56,358	$ 47,527
Less: accumulated depreciation and amortization	(16,238)	(13,293)
Property and equipment, net	40,120	34,234
Cost basis of property and equipment under capital lease	364
Land and buildings
Property, Plant and Equipment, Net [Abstract]
Property and equipment, gross	22,367	19,804
Information technology assets
Property, Plant and Equipment, Net [Abstract]
Property and equipment, gross	19,454	16,084
Construction in progress
Property, Plant and Equipment, Net [Abstract]
Property and equipment, gross	10,280	8,166
Leasehold improvements
Property, Plant and Equipment, Net [Abstract]
Property and equipment, gross	4,208	3,415
Furniture and fixtures
Property, Plant and Equipment, Net [Abstract]
Property and equipment, gross	$ 49	$ 58

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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-Publisher FASB
-Name Accounting Standards Codification
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Amount before accumulated depreciation of leased 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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