Benefit Plans (Weighted-Average Assumptions Used To Determine Net Periodic Benefit Cost) (Details)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	5.30%	5.70%	6.30%
Expected long term rate of return on plan assets, minimum rate	7.50%	7.50%	7.50%
Expected long term rate of return on plan assets, maximum rate	8.00%	8.00%	8.00%
Rate of compensation increase, minimum rate	4.00%	4.00%	3.00%
Rate of compensation increase, maximum rate	5.50%	5.50%	5.80%
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	5.00%	5.60%	6.30%
Expected long term rate of return on plan assets	4.60%	5.40%	5.40%