CONSOLIDATED STATEMENTS OF EQUITY AND REDEEMABLE NONCONTROLLING INTERESTS - USD ($) $ in Millions	Total	Class A Common Stock	Class B Common Stock	Common Stock Class A Common Stock	Common Stock Class B Common Stock	Additional Paid-In Capital	(Accumulated Deficit) Retained Earnings	Accumulated Other Comprehensive Loss	Noncontrolling Interests
Increase (Decrease) in Temporary Equity
Net income	$ 0
BALANCE (in shares) at Dec. 31, 2016				64,558,207	25,670,684
BALANCE at Dec. 31, 2016	558			$ 1	$ 0	$ 844	$ (256)	$ (1)	$ (30)
Increase (Decrease) in Stockholders' Equity
Issuance of common stock, net of issuance costs (in shares)				12,000,000
Issuance of common stock, net of issuance costs	488					488
Dividends declared and paid on Class A and Class B Common Stock	(71)						(71)
Repurchase of Class A Common Stock (in shares)				(997,300)
Repurchases of Class A Common Stock	(30)					(30)
Class A Common Stock issued pursuant to employee benefit plans (in shares)				510,238
Class A Common Stock issued pursuant to employee benefit plans	19					19
Distributions to noncontrolling interests, net	(22)								(22)
Other comprehensive income	(1)							(1)
Net income	594						576		18
BALANCE (in shares) at Dec. 31, 2017				76,071,145	25,670,684
BALANCE at Dec. 31, 2017	1,535			$ 1	$ 0	1,321	249	(2)	(34)
Increase (Decrease) in Stockholders' Equity
Cumulative effect of adoption of new accounting standard	2						2
Net income	0
BALANCE at Dec. 31, 2018	0
Increase (Decrease) in Stockholders' Equity
Dividends declared and paid on Class A and Class B Common Stock	(74)						(74)
Repurchase of Class A Common Stock (in shares)				(7,761,529)
Repurchases of Class A Common Stock	(221)					(221)
Class A Common Stock issued pursuant to employee benefit plans (in shares)				588,107
Class A Common Stock issued pursuant to employee benefit plans	21					21
Distributions to noncontrolling interests, net	(10)								(10)
Other comprehensive income	1							1
Net income	346						341		5
BALANCE (in shares) at Dec. 31, 2018		68,897,723	25,670,684	68,897,723	25,670,684
BALANCE at Dec. 31, 2018	1,600			$ 1	$ 0	1,121	518	(1)	(39)
Increase (Decrease) in Temporary Equity
Issuance of redeemable subsidiary preferred equity, net of issuance costs	985
Noncontrolling interests acquired in a business combination	380
Distributions to noncontrolling interests, net	(38)
Redemption of redeemable subsidiary preferred equity, net of fees	(297)
Net income	48
BALANCE at Dec. 31, 2019	1,078
Increase (Decrease) in Stockholders' Equity
Dividends declared and paid on Class A and Class B Common Stock	(73)						(73)
Class B Common Stock converted into Class A Common Stock (in shares)				943,002	(943,002)
Class B Common Stock converted into Class A Common Stock	0
Repurchase of Class A Common Stock (in shares)				(4,555,487)
Repurchases of Class A Common Stock	(145)					(145)
Class A Common Stock issued pursuant to employee benefit plans (in shares)				1,544,872
Class A Common Stock issued pursuant to employee benefit plans	35					35
Noncontrolling Interest, Increase from Business Combination	248								248
Distributions to noncontrolling interests, net	(27)								(27)
Other comprehensive income	(1)							(1)
Net income	105
Net income	57						47		10
BALANCE (in shares) at Dec. 31, 2019		66,830,110	24,727,682	66,830,110	24,727,682
BALANCE at Dec. 31, 2019	$ 1,694			$ 1	$ 0	$ 1,011	$ 492	$ (2)	$ 192