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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)

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- Definition 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. + Details
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