CONSOLIDATED STATEMENTS OF CHANGES IN OWNERS' EQUITY AND SERIES A PREFERRED STOCK - USD ($) shares in Thousands, $ in Millions	Total	Cumulative Effect, Period of Adoption, Adjustment [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Additional Paid-in Capital [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]	Retained Earnings (Accumulated Deficit) [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Shares [Member]	Noncontrolling Interests [Member]	Series A Preferred Stock [Member]	Series A Preferred Stock [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance at Dec. 31, 2020	$ 5,903.2	$ (448.3)	$ 0.2	$ 4,839.9	$ (448.3)	$ (1,893.5)	$ (141.8)	$ (150.9)	$ 3,249.3
Balance (in shares) at Dec. 31, 2020			228,062					6,731
Series A Preferred Stock at Dec. 31, 2020										$ 301.4	$ 448.3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Compensation on equity grants	15.0			15.0
Distribution equivalent rights	(0.4)			(0.4)
Shares issued under compensation program (in shares)			878
Shares tendered for tax withholding obligations	(8.6)							$ (8.6)
Shares tendered for tax withholding obligations (in shares)			(285)					285
Series A Preferred Stock dividends
Preferred stock dividends	(21.8)					(21.8)
Dividends in excess of retained earnings				(21.8)		21.8
Common stock dividends
Common stock dividends	(22.9)					(22.9)
Dividends in excess of retained earnings				(22.9)		22.9
Distributions to noncontrolling interests	(107.1)								(107.1)
Contributions from noncontrolling interests	2.0								2.0
Other comprehensive income (loss)	(16.6)						(16.6)
Net income (loss)	227.9					146.4			81.5
Balance at Mar. 31, 2021	5,522.4		$ 0.2	4,361.5		(1,747.1)	(158.4)	$ (159.5)	3,225.7
Balance (in shares) at Mar. 31, 2021			228,655					7,016
Series A Preferred Stock at Mar. 31, 2021										749.7
Balance at Dec. 31, 2021	5,178.7		$ 0.2	4,268.9		(1,822.3)	(230.9)	$ (204.1)	3,166.9
Balance (in shares) at Dec. 31, 2021			228,221					7,884
Series A Preferred Stock at Dec. 31, 2021										749.7
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Compensation on equity grants	13.5			13.5
Distribution equivalent rights	(1.7)			(1.7)
Shares issued under compensation program (in shares)			1,095
Shares tendered for tax withholding obligations	(22.5)							$ (22.5)
Shares tendered for tax withholding obligations (in shares)			(397)					397
Repurchases of common stock	(49.7)							$ (49.7)
Repurchases of common stock (in shares)			(738)					738
Series A Preferred Stock dividends
Preferred stock dividends	(21.8)					(21.8)
Dividends in excess of retained earnings				(21.8)		21.8
Common stock dividends
Common stock dividends	(80.0)					(80.0)
Dividends in excess of retained earnings				(80.0)		80.0
Distributions to noncontrolling interests	(72.2)								(72.2)
Contributions from noncontrolling interests	2.9								2.9
Repurchase of noncontrolling interests, net of tax	(911.0)			(53.1)					(857.9)
Other comprehensive income (loss)	(187.5)						(187.5)
Net income (loss)	168.6					88.0			80.6
Balance at Mar. 31, 2022	$ 4,017.3		$ 0.2	$ 4,125.8		$ (1,734.3)	$ (418.4)	$ (276.3)	$ 2,320.3
Balance (in shares) at Mar. 31, 2022			228,181					9,019
Series A Preferred Stock at Mar. 31, 2022										$ 749.7