Condensed Consolidated Statements of Changes in Equity (Unaudited) (Parenthetical) (USD $) In Millions	9 Months Ended
Sep. 30, 2011
Comprehensive Income:
Tax effects on unrealized losses resulting from changes in fair values of derivative instruments	$ 16
Tax effects on realized gains on derivative instruments reclassified into earnings	6
Tax effects on unrealized losses on marketable securities	3
Tax effects on Change in funded status of post-retirement benefit obligations	1
Accumulated Other Comprehensive Income (Loss) [Member]
Comprehensive Income:
Tax effects on unrealized losses resulting from changes in fair values of derivative instruments	16
Tax effects on realized gains on derivative instruments reclassified into earnings	6
Tax effects on unrealized losses on marketable securities	3
Tax effects on Change in funded status of post-retirement benefit obligations	1
Comprehensive Income [Member]
Comprehensive Income:
Tax effects on unrealized losses resulting from changes in fair values of derivative instruments	16
Tax effects on realized gains on derivative instruments reclassified into earnings	6
Tax effects on unrealized losses on marketable securities	3
Tax effects on Change in funded status of post-retirement benefit obligations	$ 1

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Tax effect of the gross appreciation or the gross loss, net of reclassification adjustment, in the change in value of available for sale securities during the period.

+ 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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- Definition

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

+ References

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- Definition

Tax effect on reclassification adjustment for accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges included in accumulated comprehensive income that was realized in net income during the period.

+ References

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- Definition

Tax effect on the change in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's increase (decrease) in deferred hedging gains or losses.

+ References

+ Details

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