Pension And Other Postretirement Benefits (Schedule Of Benefit Payments Expected To Be Paid And Expected Medicare Part D Subsidy Receipts) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
2012	$ 840
2013	850
2014	850
2015	860
2016	870
2017 through 2021	4,470
Total benefit payments	8,740
Gross Other Post-Retirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
2012	285
2013	285
2014	280
2015	275
2016	270
2017 through 2021	1,265
Total benefit payments	2,660
Medicare Part D Subsidy Receipts [Member]
Defined Benefit Plan Disclosure [Line Items]
2012	25
2013	30
2014	30
2015	35
2016	35
2017 through 2021	190
Total benefit payments	345
Net Other Post-Retirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
2012	260
2013	255
2014	250
2015	240
2016	235
2017 through 2021	1,075
Total benefit payments	$ 2,315