Employee Benefit Plans (Schedule Of Changes In Projected Benefit Obligations And Changes In Fair Value Of Plan) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Change in Plan Assets:
Employer contributions	$ 56,000	$ 169,000	$ 76,000
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation at beginning of year	3,596,000	3,400,000	3,162,000
Service cost	33,000	29,000	25,000
Interest cost	84,000	103,000	128,000
Participant contributions
Actuarial loss (gain)	(95,000)	302,000	367,000
Benefits paid	(171,000)	(165,000)	(164,000)
Curtailment
Settlements	(89,000)	(73,000)	(118,000)
Projected benefit obligation at end of year	3,358,000	3,596,000	3,400,000
Accumulated benefit obligation at end of year	3,199,000	3,433,000	3,283,000
Change in Plan Assets:
Fair value of assets at beginning of year	2,740,000	2,494,000	2,249,000
Actual return (loss) on assets	168,000	350,000	486,000
Employer contributions	21,000	134,000	41,000
Participant contributions
Benefits paid	(171,000)	(165,000)	(164,000)
Settlements	(89,000)	(73,000)	(118,000)
Fair value of assets at end of year	2,669,000	2,740,000	2,494,000
Funded Status:
Projected benefit obligation at end of year	(3,358,000)	(3,596,000)	(3,400,000)
Fair value of assets at end of year	2,669,000	2,740,000	2,494,000
Funded status at end of year	(689,000)	(856,000)	(906,000)
OPEB Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation at beginning of year	1,013,000	999,000	1,006,000
Service cost	5,000	6,000	6,000
Interest cost	26,000	32,000	43,000
Participant contributions	19,000	18,000	19,000
Actuarial loss (gain)	(136,000)	20,000	(5,000)
Benefits paid	(66,000)	(63,000)	(70,000)
Curtailment		1,000
Settlements
Projected benefit obligation at end of year	861,000	1,013,000	999,000
Accumulated benefit obligation at end of year
Change in Plan Assets:
Fair value of assets at beginning of year	145,000	141,000	132,000
Actual return (loss) on assets	13,000	14,000	25,000
Employer contributions	35,000	35,000	35,000
Participant contributions	19,000	18,000	19,000
Benefits paid	(66,000)	(63,000)	(70,000)
Settlements
Fair value of assets at end of year	146,000	145,000	141,000
Funded Status:
Projected benefit obligation at end of year	(861,000)	(1,013,000)	(999,000)
Fair value of assets at end of year	146,000	145,000	141,000
Funded status at end of year	$ (715,000)	$ (868,000)	$ (858,000)