Pension And Postretirement Benefits (Components Of Net Periodic Benefits Cost) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 11,710	$ 10,883
Interest cost	38,163	36,301
Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	121	114
Interest cost	588	745
Schedule Of Defined Net Periodic Benefit Cost [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	11,710	11,417	10,370
Interest cost	38,163	36,301	35,722
Expected return on plan assets	(50,620)	(43,793)	(37,312)
Amortization of prior service cost	421	451	530
Amortization of net (gain) loss	6,733	6,985	8,357
Settlement costs		2,614	172
Special termination benefits		52	428
Net periodic benefit cost	6,407	14,027	18,267
Schedule Of Defined Net Periodic Benefit Cost [Member] | Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	121	114	106
Interest cost	588	745	891
Amortization of prior service cost	(236)
Amortization of net (gain) loss	(110)	(175)	(514)
Net periodic benefit cost	$ 363	$ 684	$ 483