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, 2019	Sep. 30, 2018
Supplemental Cash Flow Information [Abstract]
Assets acquired, excluding cash	$ 8,619	$ 679
Liabilities assumed	(2,758)	(35)
Non-controlling interests assumed	(295)	0
Contingent/deferred purchase consideration	(66)	(108)
Net cash outflow for current year acquisitions	5,500	536
Interest paid	387	225
Income taxes paid, net of refunds	$ 442	$ 455