Employee Benefit Plans (Components Of Net Periodic Benefit Expense (Income) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Qualified Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost on benefit obligation	$ 17,542	$ 17,827	$ 52,626	$ 53,482
Expected return on plan assets	(21,102)	(21,483)	(63,308)	(64,451)
Amortization of net loss	4,862	2,636	14,585	7,909
Net periodic benefit expense (income)	1,302	(1,020)	3,903	(3,060)
Non-Qualified Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost on benefit obligation	860	946	2,579	2,840
Amortization of net loss	240	170	763	509
Net periodic benefit expense (income)	1,100	1,116	3,342	3,349
Postretirement Medical Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	419	360	1,259	1,081
Interest cost on benefit obligation	1,080	1,123	3,239	3,369
Amortization of prior service credit	(302)	(303)	(905)	(909)
Net periodic benefit expense (income)	$ 1,197	$ 1,180	$ 3,593	$ 3,541