v3.19.2

Employee Benefit Plans (Narrative) (Details) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 USD ($) pension_plan | Jun. 30, 2018 USD ($) | Jun. 30, 2019 USD ($) pension_plan | Jun. 30, 2018 USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |
Defined Contribution Plan, Cost | $ 2.4 | $ 2.3 | $ 6.5 | $ 6.1
Number Of Company Sponsored Union Pension Plans | pension_plan | 2 |  | 2 |
Pension Plan [Member] |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year | $ 31.6 |  | $ 31.6 |
Other Postretirement Benefits Plan [Member] |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year | $ 0.6 |  | $ 0.6 |

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