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Share-Based Payments (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020
Share-based Compensation Expense included in consolidated statements of income |  |  |  |
Share-based compensation expense | $ (55.8) | $ (49.5) | $ (128.4) | $ (118.8)
Subtotal | 59.4 | 45.5 | 137.9 | 121.9
Capitalized share-based compensation costs | (1.7) | (1.5) | (4.3) | (3.0)
Share-based compensation expense included in total costs and expenses | 57.7 | 44.0 | 133.6 | 118.9
Income tax effect | (10.9) | (7.0) | (24.9) | (20.3)
Research and development |  |  |  |
Share-based Compensation Expense included in consolidated statements of income |  |  |  |
Share-based compensation expense | 19.1 | 15.2 | 52.7 | 48.5
Selling, general and administrative |  |  |  |
Share-based Compensation Expense included in consolidated statements of income |  |  |  |
Share-based compensation expense | 40.3 | 30.3 | 85.2 | 73.4
Total share-based compensation expense, net of tax |  |  |  |
Share-based Compensation Expense included in consolidated statements of income |  |  |  |
Share-based compensation expense | $ 46.8 | $ 37.0 | $ 108.7 | $ 98.6

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