Pension Plans And Other Postretirement Benefit Plans (Components Of Net Periodic Benefit Cost) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), after Tax	$ 7,888	$ 4,233
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), after Tax	7,820	4,833
Service cost	15,757	19,045	15,551
Interest cost	26,224	23,896	24,349
Expected return on plan assets	(32,131)	(27,671)	(23,810)
Transition obligation recognition	0	0	0
Amortization of prior service cost	22	319	346
Net loss recognition	4,731	13,199	11,637
Net periodic benefit cost	14,603	28,788	28,073
Other Post-Retirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), after Tax	68	(600)
Service cost	1,844	4,144	2,804
Interest cost	5,226	5,216	5,056
Expected return on plan assets	(1,903)	(1,606)	(1,471)
Transition obligation recognition	0	0	505
Amortization of prior service cost	(1,116)	(149)	(149)
Net loss recognition	4,289	5,674	5,020
Net periodic benefit cost	$ 8,340	$ 13,279	$ 11,765