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New Accounting Standards (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Defined Benefit Plan, Service Cost | $ 2.5 | $ 2.4 | $ 7.8 | $ 8.0
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) | 1.4 | 2.8 | 5.3 | 8.4
Tax expense (benefit) | 14.0 | $ 14.4 | 19.1 | $ 38.3
Accounting Standards Update 2016-09 [Member] |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Excess tax benefit from share-based compensation, Operating activities |  |  | 30.3 |
Tax expense (benefit) | (4.8) |  | (30.3) |
Accounting Standards Update 2017-07 [Member] |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Defined Benefit Plan, Service Cost | 2.5 |  | 7.8 |
Accounting Standards Update 2016-02 [Member] |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Operating leases, Future minimum payments due | 77.6 |  | 77.6 |
Accounting Standards Update 2016-16 [Member] |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
New accounting pronouncement cumulative effect of change on equity | $ (4.1) |  | $ (4.1) |

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- Definition Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 10 -Section 55 -Paragraph 40 -Subparagraph (Note 3) -URI http://asc.fasb.org/extlink&oid=82846649&loc=d3e38371-112697 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41502-112717 + Details
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