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Share-Based Payments (Details 1) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2018 | Mar. 31, 2017
Summary of share based compensation expense associated with different programs [Abstract] |  |
Subtotal | $ 50.4 | $ 48.1
Capitalized share-based compensation costs | (3.4) | (2.7)
Share-based compensation expense included in total costs and expenses | 47.0 | 45.4
Market stock units |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |
Share-based compensation expense | 6.1 | 9.6
Time-vested restricted stock units |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |
Share-based compensation expense | 36.1 | 26.9
Cash settled performance shares |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |
Share-based compensation expense | 4.3 | 3.5
Performance units |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |
Share-based compensation expense | (0.8) | 4.5
Performance stock units settled in stock |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |
Share-based compensation expense | 0.7 | 0.0
Performance stock units settled in cash |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |
Share-based compensation expense | 0.1 | 0.0
Employee stock purchase plan |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |
Share-based compensation expense | $ 3.9 | $ 3.6

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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://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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -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=96867065&loc=d3e5070-113901 + Details
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