Goodwill, Customer Relationships and Other Intangible Assets (Details 4) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Sep. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Nov. 01, 2014	Jan. 31, 2013	Jan. 03, 2013
Goodwill [rollforward]
Goodwill at the beginning of the period		$ 20,674				$ 21,627	$ 21,627
Acquisitions		92	139
Impairment	(1,100)	0	(1,092)	0
Purchase accounting adjustments		(11)
November 1, 2014 reorganization					0
Goodwill at the end of the period		20,755	20,674			21,627	21,627
Business
Goodwill [rollforward]
Goodwill at the beginning of the period		6,363					6,363
Acquisitions		92	0
Impairment			0
Purchase accounting adjustments		0
November 1, 2014 reorganization					4,022
Goodwill at the end of the period		10,477	6,363				6,363
Consumer
Goodwill [rollforward]
Goodwill at the beginning of the period		10,348					10,348
Acquisitions		0	0
Impairment			0
Purchase accounting adjustments		0
November 1, 2014 reorganization					(70)
Goodwill at the end of the period		10,278	10,348				10,348
Wholesale
Goodwill [rollforward]
Goodwill at the beginning of the period		3,274					3,274
Acquisitions		0	0
Impairment			0
Purchase accounting adjustments		0
November 1, 2014 reorganization					(3,274)
Goodwill at the end of the period		0	3,274				3,274
Hosting
Goodwill [rollforward]
Goodwill at the beginning of the period		689					1,642
Acquisitions		0	139
Impairment			(1,092)
Purchase accounting adjustments		(11)
November 1, 2014 reorganization					(678)
Goodwill at the end of the period		$ 0	$ 689				$ 1,642