Acquisitions (Pro-Forma Information) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Revenue	$ 3,143	$ 2,981	$ 9,744	$ 9,338
Income from continuing operations	305	263	1,205	1,085
Net income attributable to the Company	298	256	1,174	1,067
Basic net income per share:
Basic net income per share - Continuing operations (in dollars per share)	$ 0.55	$ 0.47	$ 2.15	$ 1.93
Basic net income per share - Net income attributable to the Company (in dollars per share)	$ 0.55	$ 0.47	$ 2.15	$ 1.94
Diluted net income per share:
Diluted net income per share - Continuing operations (in dollars per share)	$ 0.54	$ 0.46	$ 2.13	$ 1.90
Diluted net income per share - Net income attributable to the Company (in dollars per share)	$ 0.54	$ 0.46	$ 2.12	$ 1.91
Current Fiscal Period Acquisitions [Member]
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Revenue related to acquisitions	46		104
Operating income related to acquisitions	$ 5		$ 11

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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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