Pension, Savings, And Other Employee Benefits (Schedule Of Components Of Net Periodic Benefit Cost) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Pension Plans Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 9	$ 10
Interest cost	7,379	7,882
Expected return on plan assets	(8,891)	(9,773)
Amortization of unrecognized, Prior service cost/(credit)	13	49
Amortization of unrecognized, Actuarial (gain)/loss	2,380	2,068
Net periodic benefit cost/(credit)	890	236
Other Postretirement Benefit Plans Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	27	28
Interest cost	326	317
Expected return on plan assets	(237)	(229)
Amortization of unrecognized, Prior service cost/(credit)	24	43
Amortization of unrecognized, Actuarial (gain)/loss	(142)	(233)
Net periodic benefit cost/(credit)	$ (2)	$ (74)