Goodwill and Other Intangibles (Changes in the Carrying Amount of Goodwill) (Details) - USD ($) $ in Millions		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016
Goodwill [Roll Forward]
Balance as of January 1, as reported		$ 8,369	$ 7,889
Goodwill acquired		370	62
Other adjustments	[1]	82	(6)
Balance at June 30,		$ 8,821	$ 7,945

[1] (a) The increase in 2017 primarily reflects the impact of foreign exchange.