Intangible Assets Including Goodwill (Details 4) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2015		Dec. 31, 2014
Changes in Goodwill Balances
Beginning Balance	$ 30,556		$ 31,184
Goodwill Additions	36		442
Purchase Price Adjustments	(1)		4
Divestitures	(4)		(183)
Foreign Currency Translation and Other Adjustments	(716)	[1]	(891)	[1]
Ending Balance	29,871		30,556
Goodwill impairment losses	0		0
Goodwill accumulated impairment losses	0		0
Global Business Services
Changes in Goodwill Balances
Beginning Balance	4,555	[2]	4,855	[2]
Purchase Price Adjustments			0	[2]
Divestitures			(52)	[2]
Foreign Currency Translation and Other Adjustments	(191)	[1]	(248)	[1],[2]
Ending Balance	4,364		4,555	[2]
Global Technology Services
Changes in Goodwill Balances
Beginning Balance	3,530	[2]	3,608	[2]
Goodwill Additions			11	[2]
Purchase Price Adjustments			21	[2]
Divestitures			(2)	[2]
Foreign Currency Translation and Other Adjustments	(80)	[1]	(108)	[1],[2]
Ending Balance	3,450		3,530	[2]
Software
Changes in Goodwill Balances
Beginning Balance	21,000		21,121
Goodwill Additions	36		430
Purchase Price Adjustments	(1)		(17)
Divestitures	(4)		(19)
Foreign Currency Translation and Other Adjustments	(428)	[1]	(516)	[1]
Ending Balance	20,603		21,000
Systems Hardware
Changes in Goodwill Balances
Beginning Balance	1,472		1,601
Divestitures			(110)
Foreign Currency Translation and Other Adjustments	(18)	[1]	(19)	[1]
Ending Balance	$ 1,454		$ 1,472

[1] Primarily driven by foreign currency translation.

[2] Reclassified to conform with 2015 presentation.