Benefit Plans (Weighted-Average Assumptions Used To Determine Benefit Obligations) (Details)	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.50%	5.30%	5.70%
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%	5.50%
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.30%	5.00%	5.60%
Expected long term rate of return on plan assets	5.30%	4.60%	5.40%