Employee Benefits (Schedule Of Amounts Recognized In Accumulated Other Comprehensive Income) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011		Dec. 31, 2010
Defined Benefit Plan Disclosure [Line Items]
Accumulated other comprehensive income, benefits, net of tax	$ (15,143)		$ (12,328)
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Net loss	20,325		15,791
Prior service cost	890		1,187
Total before tax	21,215	[1]	16,978	[1]
Accumulated other comprehensive income, benefits, net of tax	(12,873)		(10,300)
Post-Retirement Healthcare Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Net loss	3,523		2,825
Transition obligation			114
Prior service cost	218		404
Total before tax	3,741	[1]	3,343	[1]
Accumulated other comprehensive income, benefits, net of tax	$ (2,270)		$ 2,028

[1] For 2011, after-tax totals for pension benefits and post-retirement healthcare benefits were $12,873 and $2,270, respectively. The sum of these amounts ($15,143) is reflected in stockholders' equity as accumulated other comprehensive income. For 2010, after-tax totals for pension benefits and post-retirement healthcare benefits were $10,300 and $2,028, respectively. The sum of these amounts ($12,328) is reflected in stockholders' equity as accumulated other comprehensive income.