Acquisitions and Dispositions (Pro-Forma Information) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Business Combinations [Abstract]
Revenue	$ 4,189	$ 4,395	$ 8,891	$ 8,963
Net income attributable to the Company	$ 574	$ 488	$ 1,328	$ 1,146
Basic net income per share attributable to the Company (in dollars per share)	$ 1.13	$ 0.96	$ 2.63	$ 2.26
Diluted net income per share attributable to the Company (in dollars per share)	$ 1.12	$ 0.95	$ 2.60	$ 2.24