Adjustments to Additional Paid in Capital, Stock Issued, Issuance Costs and Other

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Affiliate Equity [Abstract]

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Noncontrolling Interest, Decrease from Transfers to Noncontrolling Interest Holders

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Amount of increase to additional paid-in capital (APIC) for recognition of cost for award under share-based payment arrangement.

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Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared, for example, but not limited to, common and preferred stock.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) $ in Millions	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Treasury Stock at Cost	Non-controlling Interests
Beginning Balance at Dec. 31, 2017	$ 4,578.5	$ 0.6	$ 808.6	$ (21.8)	$ 3,698.5	$ (663.7)	$ 756.3
Increase (Decrease) in Stockholders' Equity
Net income (loss)	631.1				394.9		236.2
Other comprehensive loss	(47.2)			(38.3)			(8.9)
Share-based compensation	33.5		33.5
Common stock issued under share-based incentive plans	(5.5)		(8.9)			3.4
Share repurchases	(414.0)					(414.0)
Dividends	(49.3)				(49.3)
Affiliate equity activity:
Affiliate equity compensation	43.7		10.9				32.8
Issuances	7.2		(5.4)				12.6
Repurchases	11.2		17.3				(6.1)
Changes in redemption value of Redeemable non-controlling interests	(148.1)		(148.1)
Transfers to Redeemable non-controlling interests	(30.0)						(30.0)
Capital contributions by Affiliate equity holders	3.7						3.7
Distributions to non-controlling interests	(293.6)						(293.6)
Ending Balance at Sep. 30, 2018	4,321.2	0.6	707.9	(60.1)	4,044.1	(1,074.3)	703.0
Beginning Balance at Jun. 30, 2018	4,357.4	0.6	679.7	(6.7)	3,935.5	(969.8)	718.1
Increase (Decrease) in Stockholders' Equity
Net income (loss)	201.9				124.9		77.0
Other comprehensive loss	(56.4)			(53.4)			(3.0)
Share-based compensation	11.7		11.7
Common stock issued under share-based incentive plans	3.3		(5.4)			8.7
Share repurchases	(113.2)					(113.2)
Dividends	(16.3)				(16.3)
Affiliate equity activity:
Affiliate equity compensation	16.0		6.1				9.9
Issuances	0.2		(0.6)				0.8
Repurchases	(2.9)		3.2				(6.1)
Changes in redemption value of Redeemable non-controlling interests	13.2		13.2
Transfers to Redeemable non-controlling interests	(6.6)						(6.6)
Capital contributions by Affiliate equity holders	1.2						1.2
Distributions to non-controlling interests	(88.3)						(88.3)
Ending Balance at Sep. 30, 2018	4,321.2	0.6	707.9	(60.1)	4,044.1	(1,074.3)	703.0
Beginning Balance at Dec. 31, 2018	4,134.9	0.6	835.6	(109.0)	3,876.8	(1,146.6)	677.5
Increase (Decrease) in Stockholders' Equity
Impact of adoption of new accounting standards (see Note 19)	(6.6)				(6.6)
Net income (loss)	209.3				(6.8)		216.1
Other comprehensive loss	(23.9)			(16.0)			(7.9)
Share-based compensation	30.7		30.7
Common stock issued under share-based incentive plans	(6.0)		(34.0)			28.0
Share repurchases	(250.7)		(7.5)			(243.2)
Dividends	(49.8)				(49.8)
Issuance costs and other	0.2		0.2
Affiliate equity activity:
Affiliate equity compensation	32.2		7.3				24.9
Issuances	11.0		(3.4)				14.4
Repurchases	11.6		11.6
Changes in redemption value of Redeemable non-controlling interests	(97.9)		(97.9)
Transfers to Redeemable non-controlling interests	(85.6)						(85.6)
Capital contributions by Affiliate equity holders	0.4						0.4
Distributions to non-controlling interests	(276.6)						(276.6)
Ending Balance at Sep. 30, 2019	3,633.2	0.6	742.6	(125.0)	3,813.6	(1,361.8)	563.2
Beginning Balance at Jun. 30, 2019	3,825.8	0.6	835.8	(95.1)	3,743.7	(1,259.7)	600.5
Increase (Decrease) in Stockholders' Equity
Net income (loss)	162.1				86.3		75.8
Other comprehensive loss	(37.1)			(29.9)			(7.2)
Share-based compensation	11.7		11.7
Common stock issued under share-based incentive plans	0.3		(0.1)			0.4
Share repurchases	(110.0)		(7.5)			(102.5)
Dividends	(16.4)				(16.4)
Affiliate equity activity:
Affiliate equity compensation	9.2		2.3				6.9
Issuances	0.3		(2.0)				2.3
Repurchases	3.9		3.9
Changes in redemption value of Redeemable non-controlling interests	(101.5)		(101.5)
Transfers to Redeemable non-controlling interests	(31.2)						(31.2)
Distributions to non-controlling interests	(83.9)						(83.9)
Ending Balance at Sep. 30, 2019	$ 3,633.2	$ 0.6	$ 742.6	$ (125.0)	$ 3,813.6	$ (1,361.8)	$ 563.2