Consolidated Statement of Equity (Parentheticals) (Unaudited) (USD $) In Millions, except Per Share data	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Statement Of Stockholders Equity Abstract
Change in losses on derivative financial instruments, tax effect	$ (15)
Change in pension benefit obligation, tax effect	$ (1)	$ 17
Cash dividends declared per share of common stock (in US dollars per share)	$ 0.96	$ 0.80

Aggregate dividends declared during the period for each share of common stock outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

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Tax effects of the net changes to accumulated comprehensive income during the period related to benefit plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph c(3)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 25

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Total tax effect of the change in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges after taxes. The change includes an entity's share of an equity investee's increase (decrease) in deferred hedging gains or losses.

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