Comprehensive Income (Details) (USD $) In Millions	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Notes to Financial Statements [Abstract]
Net Income	$ 441	$ 232	$ 749	$ 673
Oil and Gas Cash Flow Hedges [Abstract]
Realized Losses Reclassified Into Earnings	0	5	0	15
Less Tax Provision	0	(2)	0	(5)
Interest Rate Cash Flow Hedges [Abstract]
Unrealized Change in Fair Value	0	(47)	23	(141)
Less Tax Provision	0	16	(8)	49
Net Change in Other	1	1	4	2
Other Comprehensive Income (Loss)	1	(27)	19	(80)
Comprehensive Income	$ 442	$ 205	$ 768	$ 593

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Net of tax effect change in accumulated gains and losses from other sources. May include foreign currency transaction and translation adjustment, defined benefit plans adjustments, and available-for-sale securities adjustment.

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The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

+ References

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph A5

-Appendix A

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-Name Accounting Research Bulletin (ARB)

-Number 51

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-Name Accounting Research Bulletin (ARB)

-Number 51

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-Subparagraph c(3)

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-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 8, 9, 10, 11, 12, 13, 14

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The portion of consolidated profit or loss for the period, net of income taxes, which is attributable to the parent. If the entity does not present consolidated financial statements, the amount of profit or loss for the period, net of income taxes.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 19

-Article 5

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 38

-Subparagraph d

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-Name Accounting Research Bulletin (ARB)

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-Paragraph A7

-Appendix A

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-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 38

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 20

-Article 9

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 130

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-Name Emerging Issues Task Force (EITF)

-Number 87-21

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-Name Statement of Financial Accounting Standard (FAS)

-Number 95

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- Definition

This element represents Other Comprehensive Income (Loss), Net of Tax, for the period. Includes deferred gains (losses) on qualifying hedges, unrealized holding gains (losses) on available-for-sale securities, minimum pension liability, and cumulative translation adjustment.

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-Name Regulation S-X (SX)

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-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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Pre tax 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. A cash flow hedge is a hedge of the exposure to variability in the cash flows of a recognized asset or liability or a forecasted transaction that is attributable to a particular risk.

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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.

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Pre tax change in accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges. A cash flow hedge is a hedge of the exposure to variability in the cash flows of a recognized asset or liability or a forecasted transaction that is attributable to a particular risk. Includes an entity's share of an equity investee's increase (decrease) in deferred hedging gains or losses.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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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.

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