Consolidated Statements of Equity (Unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Stockholders' Equity [Abstract]
Dividends declared per common share (USD per share)	$ 0.77	$ 0.67	$ 2.01	$ 2.31
Comprehensive income attributable to redeemable noncontrolling interests	$ (58)	$ (40)	$ (161)	$ (136)