Pension Plans And Other Postretirement Benefit Plans (Components Of Net Periodic Benefit Cost) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 4,567	$ 4,984	$ 13,655	$ 14,917
Interest cost	6,895	6,531	20,695	19,734
Expected return on plan assets	(6,887)	(7,075)	(20,512)	(21,566)
Amortization of prior service cost	1	6	1	18
Net loss recognition	2,161	2,397	6,252	7,425
Net periodic benefit cost	6,737	6,843	20,091	20,528
Other Post-Retirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	806	721	2,389	2,141
Interest cost	1,530	1,292	4,623	3,915
Expected return on plan assets	(465)	(500)	(1,415)	(1,431)
Amortization of prior service cost	(300)	(287)	(924)	(853)
Net loss recognition	1,453	1,324	4,312	3,879
Net periodic benefit cost	$ 3,024	$ 2,550	$ 8,985	$ 7,651