Commitments and Contingencies (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2011
Commitments and Contingencies (Textuals) [Abstract]
Accrued liability for legal contingencies	$ 11
Maximum expected contractual liquidated damages under long term contracts	5.7
Validity of pipeline license	21 years
Percentage of combined ownership held by the plaintiff in the company	65.00%
Undiscounted reserve for environmental remediation	131
Alcoa [Member]
Loss Contingencies [Line Items]
Maximum expected contractual general damages under long term contracts	158
Oswal [Member]
Loss Contingencies [Line Items]
Maximum expected contractual general damages under long term contracts	$ 491

Commitments and Contingencies.

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Loss contingency estimate of possible loss general damages.

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Percentage of combined ownership held by the plaintiff in the company.

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Validity of pipeline license.

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The estimated aggregate undiscounted amount of the accrual for environmental loss contingencies as of the balance sheet date.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 30

-Section 50

-Paragraph 7

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-Publisher AICPA

-Name Statement of Position (SOP)

-Number 96-1

-Paragraph 161

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section Y

-Paragraph Question 1

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-Name Accounting Standards Codification

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The carrying amount as of the balance sheet date of the combined total of loss contingency liabilities.

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-Name Statement of Financial Accounting Standard (FAS)

-Number 5

-Paragraph 9, 10, 11, 12

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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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