Supplemental Disclosures to the Consolidated Statements of Cash Flows (Additional Information Concerning Acquisitions, Interest And Income Taxes Paid) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Supplemental Cash Flow Information [Abstract]
Assets acquired, excluding cash	$ 121	$ 636
Liabilities assumed	(4)	(51)
Contingent/deferred purchase consideration	(29)	(154)
Net cash outflow for acquisitions	88	431
Interest paid	148	126
Income taxes paid, net of refunds	$ 417	$ 335