Share-Based Payments (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Share-based Compensation Expense included in consolidated statements of income
Subtotal	$ 42.8	$ 36.4	$ 93.2	$ 84.5
Capitalized share-based compensation costs	(2.8)	(2.4)	(6.2)	(5.1)
Share-based compensation expense included in total costs and expenses	40.0	34.0	87.0	79.4
Income tax effect	(6.5)	(8.5)	(14.1)	(20.9)
Research and development
Share-based Compensation Expense included in consolidated statements of income
Share-based compensation expense	(17.6)	(17.5)	(39.5)	(36.2)
Selling, general and administrative
Share-based Compensation Expense included in consolidated statements of income
Share-based compensation expense	(25.2)	(18.9)	(53.7)	(48.3)
Total share-based compensation expense, net of tax
Share-based Compensation Expense included in consolidated statements of income
Share-based compensation expense	$ (33.5)	$ (25.5)	$ (72.9)	$ (58.5)

Share based compensation expense included in costs and expenses.

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- Definition

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
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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.

+ References

No definition available.

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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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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

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-Publisher FASB
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