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Basis of Presentation and Summary of Significant Accounting Policies (Details) $ in Millions | 6 Months Ended |
--- | --- | ---
Jun. 30, 2019 USD ($) Segment | Dec. 31, 2018 USD ($)
Basis of Presentation and Summary of Significant Accounting Policies [Abstract] |  |
Number of reportable segments | Segment | 4 |
Recently Adopted Accounting Standards [Abstract] |  |
Operating liabilities | $ 57.9 |
Right-of-use assets | 47.1 |
ASU 2016-02 [Member] |  |
Recently Adopted Accounting Standards [Abstract] |  |
Operating liabilities |  | $ 61.4
Right-of-use assets |  | 50.5
Deferred charges |  | 10.9
ASU 2018-02 [Member] |  |
Recently Adopted Accounting Standards [Abstract] |  |
Reclassification of certain tax effects from accumulated other comprehensive income |  | 0.0
ASU 2018-02 [Member] | Retained Earnings [Member] |  |
Recently Adopted Accounting Standards [Abstract] |  |
Reclassification of certain tax effects from accumulated other comprehensive income | 10.9 | 10.9
ASU 2018-02 [Member] | Accumulated Other Comprehensive Loss [Member] |  |
Recently Adopted Accounting Standards [Abstract] |  |
Reclassification of certain tax effects from accumulated other comprehensive income | $ (10.9) | $ (10.9)

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