Employee Benefit Plans (Schedule Of Restricted Stock And Restricted Stock Units Activity) (Details) (Restricted Stock Units RSU And Restricted Stock Shares [Member], USD $)	12 Months Ended
	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Restricted Stock Units RSU And Restricted Stock Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares outstanding at beginning of year, Shares	1,463,298		1,443,265		1,206,526
Granted, Shares	571,163		599,996		656,887
Vested, Shares	(504,813)		(444,905)		(327,777)
Forfeited, Shares	(266,430)		(135,058)		(92,371)
Restricted shares outstanding at end of year, Shares	1,263,218		1,463,298		1,443,265
Restricted shares outstanding at beginning of year, Grant Date Fair Value	$ 16.93	[1]	$ 21.55	[1]	$ 31.73	[1]
Granted, Grant Date Fair Value	$ 12.77	[1]	$ 12.01	[1]	$ 7.12	[1]
Vested, Grant Date Fair Value	$ 19.87	[1]	$ 25.10	[1]	$ 33.69	[1]
Forfeited, Grant Date Fair Value	$ 12.55	[1]	$ 17.48	[1]	$ 8.90	[1]
Restricted shares outstanding at end of year, Grant Date Fair Value	$ 14.80	[1]	$ 16.93	[1]	$ 21.55	[1]

[1] Represents the average grant date market value, which is based on the quoted market price of the common stock on the business day prior to the date of grant.