Retirement Benefits (Schedule Of Expected Payments From Qualified Trust And Company Funds) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012
Pension Benefits [Member] \| Paid From Qualified Trust [Member]
Defined Benefit Plan Disclosure [Line Items]
2013	$ 229
2014	236
2015	239
2016	245
2017	248
2018 - 2022	1,279
Pension Benefits [Member] \| Paid From Company Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
2013	3
2014	3
2015	3
2016	3
2017	3
2018 - 2022	13
Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
2013, Federal Subsidy	3
2014, Federal Subsidy	3
2015, Federal Subsidy	4
2016, Federal Subsidy	4
2017, Federal Subsidy	4
2018 - 2022, Federal Subsidy	19
Postretirement Benefits [Member] \| Paid From Qualified Trust [Member]
Defined Benefit Plan Disclosure [Line Items]
2013	58
2014	60
2015	62
2016	65
2017	68
2018 - 2022	384
Postretirement Benefits [Member] \| Paid From Company Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
2013	2
2014	2
2015	2
2016	2
2017	2
2018 - 2022	$ 11

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Amount of benefits expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

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Amount of benefits expected to be paid in the next fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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Amount of benefits expected to be paid in the fifth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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Amount of benefits expected to be paid in the fourth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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Amount of benefits expected to be paid in the third fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the second fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of the prescription drug subsidy receipts to be received after the fifth fiscal year following the latest fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

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Amount of the prescription drug subsidy receipts to be received in the next fiscal year following the latest fiscal year.

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Amount of the prescription drug subsidy receipts to be received in the third fiscal year following the latest fiscal year.

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