Pension Plans, Retirement Benefits and Savings Plans (details) - Level 3 Changes (Pension Plans [Member], USD $) In Millions, unless otherwise specified								12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Level 3 [Member]	Dec. 31, 2012 Level 3 [Member]	Dec. 31, 2013 Other investments [Member]	Dec. 31, 2012 Other investments [Member]	Dec. 31, 2013 Other investments [Member] Level 3 [Member]	Dec. 31, 2012 Other investments [Member] Level 3 [Member]
Changes in Level 3 fair value category [Roll Forward]
Fair value of plan assets, balance, beginning of year	$ 3,203	$ 2,859	$ 2,500	$ 4	$ 6	$ 4	$ 6	$ 6	$ 18
Actual return on plan assets, relating to assets still held								1	2
Level 3 fair value category sales								(3)	(12)
Gross transfers out of Level 3									(2)
Fair value of plan assets, balance, end of year	$ 3,203	$ 2,859	$ 2,500	$ 4	$ 6	$ 4	$ 6	$ 4	$ 6

Defined benefit plan transfers out of Level 3. For example, transfers due to changes in the observability of significant inputs.

No definition available.

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- Definition

Actual return on plan assets, separately identifying the amount related to assets still held at the reporting date.

+ 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 (d)(iv)(02)(A)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)(iv)(02)(A)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e2446-114920

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- Details

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- Definition

The amount of decrease in the plan assets attributed to the sale, liquidation, spin-off or other divestiture of a corporate division or subsidiary.

+ References

+ Details

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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

+ 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 (b)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Section 35

-Paragraph 50

-URI http://asc.fasb.org/extlink&oid=29635418&loc=d3e12355-114930

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