Basis of Presentation - Redeemable Non Controlling Interest (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Redeemable Noncontrolling Interest [Roll Forward]
Balance at beginning of period	$ 78	$ 196
Net income (loss) attributable to redeemable noncontrolling interests	15	12
Other comprehensive income (loss)	(3)	(2)
Noncontrolling interest tender offer redemption	0	(46)
Redemption value measurement adjustment	21	10
Reclassification of noncontrolling interest to permanent equity	0	(82)
Dividends declared	0	(25)
Balance at end of period	$ 111	$ 63