Share-Based Payments (Details 1) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Summary of share based compensation expense associated with different programs
Share-based compensation expense	$ 138.1	$ 169.4	$ 183.2
Subtotal	169.7	204.4	207.3
Capitalized share-based compensation costs	(9.6)	(14.6)	(11.0)
Share-based compensation expense included in total costs and expenses	160.1	189.8	196.3
Market stock units
Summary of share based compensation expense associated with different programs
Share-based compensation expense	22.4	38.4	38.1
Time-vested restricted stock units
Summary of share based compensation expense associated with different programs
Share-based compensation expense	107.3	120.0	119.0
Cash settled performance units
Summary of share based compensation expense associated with different programs
Share-based compensation expense	18.4	16.3	22.4
Performance Units [Member]
Summary of share based compensation expense associated with different programs
Share-based compensation expense	12.3	18.6	13.9
Employee stock purchase plan
Summary of share based compensation expense associated with different programs
Share-based compensation expense	$ 9.3	$ 11.1	$ 13.9

Share based compensation expense included in costs and expenses.

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Summary of share-based compensation expense associated with different programs.

+ References

No definition available.

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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-Publisher FASB
-Name Accounting Standards Codification
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The amount of expense, net of income tax, 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.

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

+ References

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