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Share-Based Payments (Details 1) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	$ 49.0	$ 46.7
Subtotal	49.5	50.4
Capitalized share-based compensation costs	(3.3)	(3.4)
Share-based compensation expense included in total costs and expenses	46.2	47.0
Market stock units
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	7.7	6.1
Time-vested restricted stock units
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	34.7	36.1
Cash settled performance shares
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	(1.0)	4.3
Performance units
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	0.5	(0.8)
Performance stock units settled in stock
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	2.0	0.7
Performance stock units settled in cash
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	1.0	0.1
Employee stock purchase plan
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	$ 4.6	$ 3.9

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Share based compensation expense included in costs and expenses.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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