Pension Plans And Other Post-Retirement Benefits (Schedule Of Accumulated And Projected Benefit Obligations) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Projected Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$ 310,381	$ 281,964
Fair value of plan assets	266,461	239,007
Accumulated Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation	290,522	264,876
Fair value of plan assets	$ 266,461	$ 239,007

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Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets.

+ References

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Amount of plan asset for defined benefit plan with accumulated benefit obligation in excess of plan assets.

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