Sale of Data Centers and Colocation Business (Details 2) - USD ($) $ in Millions	3 Months Ended			6 Months Ended	8 Months Ended	9 Months Ended
	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2017	Jun. 30, 2017	Sep. 30, 2017	Sep. 30, 2016
Sale Leaseback Transaction [Line Items]
Revenues	$ 4,034		$ 4,382			$ 12,333	$ 13,181
Cost of services and products (exclusive of depreciation and amortization)	(1,927)		(1,996)			(5,705)	(5,845)
Selling, general and administrative	(710)		(798)			(2,404)	(2,450)
Depreciation	(910)		(995)			(2,739)	(2,958)
Interest expense	(362)		(327)			(1,000)	(998)
Income tax expense	(47)		(97)			(214)	(362)
NET INCOME	92		$ 152			272	$ 584
Cyxtera Technologies
Sale Leaseback Transaction [Line Items]
Revenues	19					31
Cost of services and products (exclusive of depreciation and amortization)	6					9
Selling, general and administrative	15					(102)
Depreciation expense on assets reclassified from held-for-sale	0					(44)
Depreciation	(19)					(29)
Interest expense	(17)					(25)
Income tax expense	(3)					60
NET INCOME	$ 1					$ (100)
Colocation Business and Data Centers
Sale Leaseback Transaction [Line Items]
Income tax expense		$ (18)		$ (47)	$ (65)