Equity And Comprehensive Income (Detailed Activities Of Accumulated Other Comprehensive Income) (Details) (USD $)	3 Months Ended		6 Months Ended			12 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011		Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Equity, Comprehensive Income, And Accumulated Other Comprehensive Income
Beginning Balance AOCI December 31, 2010, Defined Benefit Plans - Before Tax			$ (31,304,000)
Beginning Balance AOCI December 31, 2010, Defined Benefit Plans - Tax (Expense) Benefit			11,896,000
Beginning Balance AOCI December 31, Defined Benefit Plans - After-Tax			(19,408,000)
Beginning Balance AOCI December 31, 2010, FSIRS - Before-Tax			(18,349,000)
Beginning Balance AOCI December 31, 2010, FSIRS - Tax (Expense) Benefit			6,973,000
Beginning Balance AOCI December 31, 2010, FSIRS - After-Tax			(11,376,000)
Current period change, Defined Benefit Plans - Before-Tax			1,032,000
Current period change, Defined Benefit Plans - Tax (Expense) Benefit	(196,000)	(209,000)	(392,000)		(419,000)	(1,714,000)	1,567,000
Current period change, Defined Benefit Plans - After-Tax	320,000	342,000	640,000	[1]	683,000	2,799,000	(2,554,000)
Current period change, FSIRS - Before-Tax			(2,560,000)
Current period change, FSIRS - Tax (Expense) Benefit			973,000
Current period change, FSIRS - After-Tax	(2,184,000)	(12,569,000)	(1,587,000)	[2]	(13,181,000)	218,000	(13,181,000)
Beginning balance AOCI December 31,2010			(30,784,000)
AOCI, current period charge			(947,000)
Ending Balance AOCI June 30, 2011, Defined Benefit Plans - Before Tax	(30,272,000)		(30,272,000)			(30,272,000)
Ending Balance AOCI June 30, 2011, Defined Benefit Plans - Tax (Expense) Benefit	11,504,000		11,504,000			11,504,000
Ending Balance AOCI June 30, 2011, Defined Benefit Plans - After Tax	(18,768,000)		(18,768,000)			(18,768,000)
Ending Balance AOCI June 30, 2011, FSIRS - Before-Tax	(20,909,000)		(20,909,000)			(20,909,000)
Ending Balance AOCI June 30, 2011, FSIRS - Tax (Expense) Benefit	7,946,000		7,946,000			7,946,000
Ending Balance AOCI June 30, 2011, FSIRS - After-Tax	(12,963,000)		(12,963,000)			(12,963,000)
Ending Balance AOCI June 30, 2011	(31,731,000)		(31,731,000)			(31,731,000)
FSIRS realized and unrealized gains (losses), Net of Tax			(1,950,000)
Amounts reclassified to net income, net of tax (Note 4)	182,000		363,000			423,000
Amount of FSIRS existing AOCI losses expected to reclassified income in next 12 months	$ 904,000		$ 904,000			$ 904,000

[1] Net actuarial gain (loss), less amortization of unamortized benefit plan cost

[2] FSIRS unrealized loss of $1,950,000 recognized in other comprehensive income less the portion of the previous FSIRS realized loss that was reclassified to net income in the current period ($363,000).