Pension, Savings, And Other Employee Benefits (Schedule Of Net Periodic Cost) (Details) (USD $)	3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		12 Months Ended		6 Months Ended	12 Months Ended
	Jun. 30, 2011 Pension Benefits [Member]	Jun. 30, 2010 Pension Benefits [Member]	Jun. 30, 2011 Pension Benefits [Member]	Jun. 30, 2010 Pension Benefits [Member]	Jun. 30, 2011 Other Benefits [Member]	Jun. 30, 2010 Other Benefits [Member]	Jun. 30, 2011 Other Benefits [Member]	Jun. 30, 2010 Other Benefits [Member]	Dec. 31, 2011 Non-Qualified Plans [Member]	Dec. 31, 2010 Non-Qualified Plans [Member]	Jun. 30, 2011 Savings Plan [Member]	Dec. 31, 2010 Savings Plan [Member]
Service cost	$ 4,301,000	$ 3,778,000	$ 8,602,000	$ 7,556,000	$ 144,000	$ 136,000	$ 288,000	$ 272,000
Interest cost	8,147,000	7,836,000	16,294,000	15,673,000	552,000	595,000	1,104,000	1,190,000
Expected return on plan assets	(11,724,000)	(11,879,000)	(23,446,000)	(23,759,000)	(297,000)	(287,000)	(596,000)	(575,000)
Amortization of unrecognized, Transition obligation					246,000	247,000	492,000	494,000
Amortization of unrecognized, Prior service cost/(credit)	104,000	67,000	208,000	134,000	(2,000)	(2,000)	(4,000)	(4,000)
Amortization of unrecognized, Actuarial (gain)/loss	5,027,000	3,772,000	10,054,000	7,543,000	(260,000)	(216,000)	(520,000)	(431,000)
Net periodic benefit cost	5,855,000	3,574,000	11,712,000	7,147,000	383,000	473,000	764,000	946,000
Pension contributions										4,500,000		1,200,000
Expected pension contribution									5,100,000
Expected contributions											$ 1,300,000