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	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Supplemental Cash Flow Information [Abstract]
Assets acquired, excluding cash	$ 131	$ 128
Liabilities Assumed	(31)
Liabilities assumed	(42)	(17)
Contingent/deferred purchase consideration	18	13
Net cash outflow for current year acquisitions	82	98
Deferred purchase consideration from prior year acquisitions	47	15
Net cash outflow for acquisitions	129	113
Interest paid	92	100
Income taxes (refunded)/paid	$ 160	$ (112)