Acquisitions and Dispositions (Pro-Forma Information) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Business Combinations [Abstract]
Revenue	$ 17,301	$ 17,323	$ 17,106
Net income attributable to the Company	$ 2,021	$ 1,877	$ 1,302
Basic net income per share attributable to the Company (in dollars per share)	$ 3.99	$ 3.71	$ 2.58
Diluted net income per share attributable to the Company (in dollars per share)	$ 3.95	$ 3.67	$ 2.55