Pension Plans And Other Postretirement Benefits (Schedule Of Components Of Pension And Postretirement Benefits Expense) (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	$ 12,830	$ 11,271	$ 10,568
Interest cost	32,933	31,844	32,967
Expected return on assets	(48,645)	(41,941)	(42,341)
Amortization of net transition asset		(9)	(10)
Amortization of prior service benefit	(953)	(986)	(984)
Amortization of net loss	26,137	17,410	12,348
Benefits expense (income)	22,302	17,589	12,548
Discount rate	5.40%	5.77%	6.45%
Expected return on plan assets	8.19%	8.19%	8.69%
Rate of compensation increase	3.93%	3.90%	4.11%
Domestic Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	11,169	9,577	8,544
Interest cost	30,945	29,934	30,608
Expected return on assets	(48,235)	(41,630)	(42,080)
Amortization of net transition asset		(9)	(10)
Amortization of prior service benefit	(1,009)	(1,038)	(1,039)
Amortization of net loss	24,934	16,222	11,440
Benefits expense (income)	17,804	13,056	7,463
Discount rate	5.45%	5.86%	6.50%
Expected return on plan assets	8.25%	8.25%	8.75%
Rate of compensation increase	4.11%	4.11%	4.33%
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	263	382	438
Interest cost	3,393	3,564	3,769
Expected return on assets	(509)	(526)	(571)
Amortization of prior service benefit	(697)	(1,704)	(7,572)
Amortization of net loss	2,409	1,688	1,096
Benefits expense (income)	$ 4,859	$ 3,404	$ (2,840)
Discount rate	5.30%	5.70%	6.55%
Expected return on plan assets	7.00%	7.00%	7.00%
Rate of compensation increase	4.00%	4.00%	4.25%