Acquisitions (Pro-Forma Information) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Revenue	$ 3,306	$ 3,152	$ 6,591	$ 6,348
Income from continuing operations	440	406	900	823
Net income attributable to the Company	431	393	877	812
Basic net income per share:
Basic net income per share - Continuing operations (in dollars per share)	$ 0.79	$ 0.72	$ 1.60	$ 1.46
Basic net income per share - Net income attributable to the Company (in dollars per share)	$ 0.79	$ 0.71	$ 1.60	$ 1.48
Diluted net income per share:
Diluted net income per share - Continuing operations (in dollars per share)	$ 0.78	$ 0.71	$ 1.58	$ 1.44
Diluted net income per share - Net income attributable to the Company (in dollars per share)	$ 0.78	$ 0.70	$ 1.58	$ 1.45
Current Fiscal Period Acquisitions [Member]
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Revenue related to acquisitions	38		59
Operating income related to acquisitions	$ 5		$ 6

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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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