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MTBE Cases pending in MDL Court.

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Superfund Sites

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Best estimate of the reasonably possible loss exposure in excess of the amount accrued for remediation, site restoration, postclosure, monitoring commitments, or other exit costs associated with the sale, disposal or abandonment of a particular property resulting from unanticipated contamination of the assets.

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The number of claims settled and dismissed during the period.

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Commitments and Contingencies (Narrative) (Details) (USD $)	1 Months Ended		9 Months Ended
	Nov. 30, 2010	Sep. 30, 2010	Sep. 30, 2011 Claims Location Cases FinancialInstitutions
Commitments and Contingencies (Narrative) (Details) [Abstract]
Superfund Sites			28
MBTE cases remaining			11
MTBE Cases Settled or Dismissed			88
MTBE Cases pending in MDL Court			11
Accrued contingencies for legal matters			$ 40,000,000
Related insurance receivables, for our outstanding legal proceedings			2,000,000
Damages have been alleged in the remaining El Paso Marketing L.P. lawsuits			140,000,000
MTBE cases that are not insured			9
Amount paid from government sponsored programs or contractual arrangements			19,000,000
Loss contingency, range of possible loss, Minimum			186,000,000
Loss contingency, range of possible loss, Maximum			327,000,000
Total estimated remediation expenditures for 2011			20,000,000
Environmental Capital Expenditures For 2011 Through 2015			27,000,000
Guarantee obligations, maximum exposure			700,000,000
Guarantees and indemnification arrangements recorded			17,000,000
Estimated increase in revenue due to increase in Tariff rates		100,000,000
Estimated Increase In Revenue Due To Increase In Tariff Rates Minimum	60,000,000
Estimated Increase In Revenue Due To Increase In Tariff Rates Maximum	70,000,000
Environmental Legal Reserve [Member]
Site Contingency [Line Items]
Environmental accrual			3,000,000
Environmental Remediation Reserve [Member]
Site Contingency [Line Items]
Environmental accrual			$ 183,000,000