Pension And Other Postretirement Benefits (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Pension And Other Postretirement Benefits [Abstract]
Vesting percentage			100.00%
Required term of service to be eligible for plan match			one year of service and 1,000 hours of service
Award vesting period			3 years
Employer contributions	$ 10.0	$ 10.0	$ 21.6	$ 21.8
Expected employer contributions remainder of year	$ 20.0		$ 20.0