Acquisitions (Pro-Forma Information) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Sep. 30, 2010	Jun. 30, 2012	Jun. 30, 2011
Acquisitions [Abstract]
Revenue	$ 3,030	$ 2,974	$ 6,092	$ 5,908
Income from continuing operations	340	289	695	605
Net income attributable to the Company	$ 330	$ 285	$ 678	$ 606
Basic net income per share - Continuing operations (in dollars per share)	$ 0.61	$ 0.51	$ 1.25	$ 1.08
Basic net income per share - Net income attributable to the Company (in dollars per share)	$ 0.60	$ 0.52	$ 1.24	$ 1.10
Diluted net income per share - Continuing operations (in dollars per share)	$ 0.60	$ 0.50	$ 1.23	$ 1.06
Diluted net income per share - Net income attributable to the Company (in dollars per share)	$ 0.60	$ 0.51	$ 1.23	$ 1.09

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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