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	Series A Preferred Stock 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		$ 448.3
Balance (in shares) at Dec. 31, 2020			228,062					6,731
Series A Preferred Stock at Dec. 31, 2020										$ 301.4
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Compensation on equity grants	44.6			44.6
Distribution equivalent rights	(2.4)			(2.4)
Shares issued under compensation program (in shares)			1,294
Shares tendered for tax withholding obligations	(13.1)							$ (13.1)
Shares tendered for tax withholding obligations (in shares)			(393)					393
Series A Preferred Stock dividends
Preferred stock dividends	(65.5)					(65.5)
Dividends in excess of retained earnings				(65.5)		65.5
Common stock dividends
Common stock dividends	(68.6)					(68.6)
Dividends in excess of retained earnings				(68.6)		68.6
Distributions to noncontrolling interests	(334.2)								(334.2)
Contributions from noncontrolling interests	13.2								13.2
Other comprehensive income (loss)	(300.3)						(300.3)
Net income (loss)	671.3					384.8			286.5
Balance at Sep. 30, 2021	5,399.9		$ 0.2	4,299.7		(1,508.7)	(442.1)	$ (164.0)	3,214.8
Balance (in shares) at Sep. 30, 2021			228,963					7,124
Series A Preferred Stock at Sep. 30, 2021										749.7
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		$ 448.3
Balance at Jun. 30, 2021	5,396.5		$ 0.2	4,330.8		(1,690.9)	(294.4)	$ (159.5)	3,210.3
Balance (in shares) at Jun. 30, 2021			228,655					7,016
Series A Preferred Stock at Jun. 30, 2021										749.7
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Compensation on equity grants	14.7			14.7
Distribution equivalent rights	(1.1)			(1.1)
Shares issued under compensation program (in shares)			416
Shares tendered for tax withholding obligations	(4.5)							$ (4.5)
Shares tendered for tax withholding obligations (in shares)			(108)					108
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	(110.4)								(110.4)
Contributions from noncontrolling interests	9.1								9.1
Other comprehensive income (loss)	(147.7)						(147.7)
Net income (loss)	288.0					182.2			105.8
Balance at Sep. 30, 2021	5,399.9		$ 0.2	4,299.7		(1,508.7)	(442.1)	$ (164.0)	3,214.8
Balance (in shares) at Sep. 30, 2021			228,963					7,124
Series A Preferred Stock at Sep. 30, 2021										749.7
Balance at Jun. 30, 2021	5,396.5		$ 0.2	4,330.8		(1,690.9)	(294.4)	$ (159.5)	3,210.3
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	41.8			41.8
Distribution equivalent rights	(5.2)			(5.2)
Shares issued under compensation program (in shares)			1,580
Shares tendered for tax withholding obligations	(31.1)							$ (31.1)
Shares tendered for tax withholding obligations (in shares)			(526)					526
Repurchases of common stock	(196.8)							$ (196.8)
Repurchases of common stock (in shares)			(3,017)					3,017
Series A Preferred Stock dividends
Preferred stock dividends	(30.0)					(30.0)
Dividends in excess of retained earnings				(30.0)		30.0
Deemed dividends - repurchase of Series A Preferred Stock	(215.5)			(215.5)
Common stock dividends
Common stock dividends	(239.1)					(239.1)
Dividends in excess of retained earnings				(239.1)		239.1
Redemption of Series A preferred Stock										(749.7)
Distributions to noncontrolling interests	(234.0)								(234.0)
Contributions from noncontrolling interests	13.9								13.9
Repurchase of noncontrolling interests, net of tax	(911.0)			(53.1)					(857.9)
Other comprehensive income (loss)	224.2						224.2
Net income (loss)	1,135.5					877.5			258.0
Balance at Sep. 30, 2022	4,731.4		$ 0.2	3,767.8		(944.8)	(6.7)	$ (432.0)	2,346.9
Balance (in shares) at Sep. 30, 2022			226,258					11,427
Series A Preferred Stock at Sep. 30, 2022										0.0
Balance at Dec. 31, 2021	5,178.7		$ 0.2	4,268.9		(1,822.3)	(230.9)	$ (204.1)	3,166.9
Balance at Jun. 30, 2022	4,400.9		$ 0.2	3,834.4		(1,137.9)	(276.4)	$ (350.4)	2,331.0
Balance (in shares) at Jun. 30, 2022			227,062					10,142
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Compensation on equity grants	14.4			14.4
Distribution equivalent rights	(1.7)			(1.7)
Shares issued under compensation program (in shares)			481
Shares tendered for tax withholding obligations	(8.6)							$ (8.6)
Shares tendered for tax withholding obligations (in shares)			(128)					128
Repurchases of common stock	(73.0)							$ (73.0)
Repurchases of common stock (in shares)			(1,157)					1,157
Series A Preferred Stock dividends
Dividends in excess of retained earnings				(79.3)		79.3
Common stock dividends
Common stock dividends	(79.3)					(79.3)
Distributions to noncontrolling interests	(75.2)								(75.2)
Contributions from noncontrolling interests	4.9								4.9
Other comprehensive income (loss)	269.7						269.7
Net income (loss)	279.3					193.1			86.2
Balance at Sep. 30, 2022	4,731.4		$ 0.2	3,767.8		(944.8)	(6.7)	$ (432.0)	2,346.9
Balance (in shares) at Sep. 30, 2022			226,258					11,427
Series A Preferred Stock at Sep. 30, 2022										$ 0.0
Balance at Jun. 30, 2022	$ 4,400.9		$ 0.2	$ 3,834.4		$ (1,137.9)	$ (276.4)	$ (350.4)	$ 2,331.0