Supplemental Disclosures To The Consolidated Statements Of Cash Flows (Additional Information Concerning Acquisitions, Interest And Income Taxes Paid) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Supplemental Cash Flow Information [Abstract]
Assets acquired, excluding cash	$ 0	$ 93
Liabilities assumed	0	(27)
Contingent/deferred purchase consideration	0	(13)
Net cash outflow for current year acquisitions	0	53
Deferred purchase consideration from prior year acquisitions	1	7
Net cash outflow for acquisitions	1	60
Interest paid	59	65
Income taxes paid	$ 85	$ 79