Sale of Data Centers and Colocation Business (Details) - USD ($) $ in Millions		3 Months Ended
	May 01, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total amount classified as assets held for sale			$ 2,343	$ 2,376
Capital lease obligations			297	305
Total liabilities associated with assets held for sale			406	419
Income tax expense			144		$ 144
Colocation Business and Data Centers
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Capital lease obligations			297
Depreciation and amortization			50
Impairment charges on assets held for sale			11
Income tax expense			15	$ 18
Colocation Business and Data Centers | Disposal Group, Held-for-sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Goodwill			1,141
Property, plant and equipment			1,068
Other intangible assets			258
Other assets			37
Impairment on assets held for sale			(11)
Total amount classified as assets held for sale			2,493
Capital lease obligations			297
Other liabilities			109
Total liabilities associated with assets held for sale			$ 406
Scenario, Forecast | Minimum | Colocation Business and Data Centers
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income tax expense		$ 75
Scenario, Forecast | Maximum | Colocation Business and Data Centers
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income tax expense		$ 150
Subsequent event | Colocation Business and Data Centers
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net proceeds from sales of data centers and colocation business	$ 1,860