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Share-Based Payments (Details 1) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Summary of share based compensation expense associated with different programs |  |  |
Share-based compensation expense | $ 138.1 | $ 169.4 | $ 183.2
Subtotal | 169.7 | 204.4 | 207.3
Capitalized share-based compensation costs | (9.6) | (14.6) | (11.0)
Share-based compensation expense included in total costs and expenses | 160.1 | 189.8 | 196.3
Market stock units |  |  |
Summary of share based compensation expense associated with different programs |  |  |
Share-based compensation expense | 22.4 | 38.4 | 38.1
Time-vested restricted stock units |  |  |
Summary of share based compensation expense associated with different programs |  |  |
Share-based compensation expense | 107.3 | 120.0 | 119.0
Cash settled performance units |  |  |
Summary of share based compensation expense associated with different programs |  |  |
Share-based compensation expense | 18.4 | 16.3 | 22.4
Performance Units [Member] |  |  |
Summary of share based compensation expense associated with different programs |  |  |
Share-based compensation expense | 12.3 | 18.6 | 13.9
Employee stock purchase plan |  |  |
Summary of share based compensation expense associated with different programs |  |  |
Share-based compensation expense | $ 9.3 | $ 11.1 | $ 13.9

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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://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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