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v3.19.1

Basis of Presentation Pension and Post-Retirement Benefits (Details) - USD ($) $ in Millions |  | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Jan. 01, 2019 | Mar. 31, 2019 | Mar. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Right of use assets |  | $ 466.2 |  |  | $ 16.8
Lease liability |  | 467.3 |  |  | $ 11.3
Reclassification out of Accumulated Other Comprehensive Income [Domain] |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification |  | $ 0.0 | $ 19.4 |  |
Accounting Standards Update 2016-02 [Member] |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Right of use assets | $ 460.7 |  |  |  |
Lease liability | 483.6 |  |  |  |
Deferred gain recognized | $ 39.4 |  |  |  |
Scenario, Forecast [Member] | Accounting Standards Update 2016-02 [Member] |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Deferred gain recognized |  |  |  | $ 4.0 |

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