Pension, Other Postretirement Benefits (OPEB) And Savings Plans (Assumptions Used To Determine The Benefit Obligations And Net Periodic Benefit Costs) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Defined Benefit Plan Disclosure [Line Items]
Expected Return on Plan Assets	8.50%
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	5.00%	5.51%	5.91%
Rate of Compensation Increase	4.61%	4.61%	4.61%
Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	5.00%	5.50%	5.90%
Rate of Compensation Increase	4.61%	4.61%	4.61%
Administrative Expense	5.00%	5.00%	5.00%
Dental Costs	6.00%	6.00%	6.00%
Total of Service Cost and Interest Cost	$ 11	$ 10	$ 11
Postretirement Benefit Obligation	155	122	137
Total of Service Cost and Interest Cost	(9)	(8)	(9)
Postretirement Benefit Obligation	$ (128)	$ (102)	$ (115)
Other Benefits [Member] | Pre-65 Medical Costs [Member]
Defined Benefit Plan Disclosure [Line Items]
Immediate Rate	8.00%	7.75%	8.50%
Ultimate Rate	5.00%	5.00%	5.00%
Year Ultimate Rate Reached	2016	2015	2015
Other Benefits [Member] | Post-65 Medical Costs [Member]
Defined Benefit Plan Disclosure [Line Items]
Immediate Rate	8.25%	8.75%	9.50%
Ultimate Rate	5.00%	5.00%	5.00%
Year Ultimate Rate Reached	2017	2016	2016
Net Periodic Benefit Cost [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	5.40%	5.91%	6.80%
Expected Return on Plan Assets	8.50%	8.50%	8.75%
Rate of Compensation Increase	4.61%	4.61%	4.61%
Net Periodic Benefit Cost [Member] | Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	5.38%	5.90%	6.80%
Expected Return on Plan Assets	8.50%	8.50%	8.75%
Rate of Compensation Increase	4.61%	4.61%	4.61%