Pension, Savings, And Other Employee Benefits (Schedule Of Components Of Net Periodic Benefit Cost) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 10	$ 9
Interest cost	6,986	7,379
Expected return on plan assets	(8,225)	(8,891)
Amortization of unrecognized, Prior service cost/(credit)	0	13
Amortization of unrecognized, Actuarial (gain)/loss	2,956	2,380
Net periodic benefit cost/(credit)	1,727	890
Other Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	33	27
Interest cost	327	326
Expected return on plan assets	(269)	(237)
Amortization of unrecognized, Prior service cost/(credit)	0	24
Amortization of unrecognized, Actuarial (gain)/loss	(91)	(142)
Net periodic benefit cost/(credit)	$ 0	$ (2)