Supplemental Disclosures to the Consolidated Statements of Cash Flows (Additional Information Concerning Acquisitions, Interest And Income Taxes Paid) (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Supplemental Cash Flow Information [Abstract]
Assets acquired, excluding cash	$ 204	$ 576
Liabilities assumed	(28)	(74)
Contingent/deferred purchase consideration	(32)	(90)
Net cash outflow for current year acquisitions	144	412
Interest paid	107	92
Income taxes paid, net of refunds	$ 349	$ 297

Business Combination, Consideration Transferred Assets Acquired

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Business Combination, Contingent and Deferred Consideration

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Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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