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