Incentive Program (Grant Value Of Restricted Stock And Units) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Grant price, per share	$ 95.2	$ 94.47	$ 87.24
Restricted stock and units settled in stock	$ 858	$ 843	$ 797
Units settled in cash	73	76	77
Total value	$ 931	$ 919	$ 874

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Value, after forfeitures, of stock or other type of equity granted of any equity-based compensation plan other than an employee stock ownership plan (ESOP).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 30

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6743629&loc=d3e3913-113898

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 30

-Section 35

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6418191&loc=d3e15009-113911

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- Definition

Share based compensation arrangement by share based payment award restricted stock and units settled in stock.

+ References

No definition available.

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- Definition

Share Based Compensation Arrangements By Share Based Payment Units Settled In Cash

+ References

No definition available.

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