Goodwill and Other Intangibles (Changes in the Carrying Amount of Goodwill) (Details) - USD ($) $ in Millions		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014
Goodwill [Roll Forward]
Balance as of January 1, as reported		$ 7,241	$ 6,893
Goodwill acquired		188	334
Other adjustments	[1]	(48)	3
Balance at June 30,		$ 7,381	$ 7,230

[1] Primarily reflects the impact of foreign exchange in each period.