Acquisitions/Divestitures (Divestitures) (Details 4) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Discontinued Operations
Impairment of long-lived asstes			$ 0
Microelectronics business
Discontinued Operations
Description of continuing involvement after transaction			The transaction includes a 10-year exclusive manufacturing sourcing agreement in which GLOBALFOUNDRIES will provide server processor semiconductor technology for use in IBM Systems. The agreement provides the company with capacity and market-based pricing for current semiconductor nodes in production and progression to nodes in the future for both development and production needs. As part of the transaction, the company will provide GLOBALFOUNDRIES with certain transition services, including IT, supply chain, packaging and test services and lab services. The initial term for these transition services is one to three years, with GLOBALFOUNDRIES having the ability to renew.
Discontinued operation, period of exclusive manufacturing agreement after disposal			10 years
Total cash consideration expected to be transferred to acquiring company		$ 1,500		$ 1,500
Other related costs		800
Cumulative pre-tax gain(loss) on sale of business			$ (4,800)
Net cash transferred	$ 515
Cash consideration payable at closing date	750		$ 750
Period of time over which cash consideration is expected to be transferred			3 years
Microelectronics business | Discontinued operations
Discontinued Operations
Pre-tax charge related to sale	$ 57	4,697	$ 108	$ 4,697
Impairment of long-lived asstes		$ 2,400
Microelectronics business | Minimum
Discontinued Operations
Discontinued operation, period of continuing involvement after disposal			1 year
Microelectronics business | Maximum
Discontinued Operations
Discontinued operation, period of continuing involvement after disposal			3 years