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Share-Based Payments (Details 1) - USD ($) $ in Millions | 3 Months Ended
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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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- 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 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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=115993241&loc=d3e301413-122809 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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