Additional Information (Schedule of Additional Information) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Additional Information [Abstract]
Research and development expense	$ 429	$ 423	$ 433
Advertising expense	405	448	439
Foreign currency net transaction losses	272	102	174
Interest expense	1,069	1,132	1,170
Interest income	(178)	(124)	(118)
Interest expense, net	891	1,008	1,052
Rent expense	$ 284	$ 286	$ 336