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Amount represents financing facility entered for Ruby pipeline project in which the company will receive funding $1.5 billion to construct the Ruby pipeline.

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Letters of Credit and Surety Bonds Outstanding.

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- Definition

Amount represents letters of credit securing the company's recorded obligations related to price risk management activities.

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Line of credit facility increased amount.

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Line of credit facility increased interest rate description.

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Line of credit facility reduced amount.

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Credit facility that matured.

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Maximum percentage of dropping in ownership interest.

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- Definition

Refinanced revolving credit facilities.

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Amount of the required periodic payments applied to principal.

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Gross amount of debt extinguished.

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Amount represents the difference between the fair value of the payments made and the carrying amount of the debt at the time of its extinguishment.

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Amount borrowed under the credit facility as of the balance sheet date.

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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Increase for additional borrowings on the credit facility during the period.

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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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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Debt, Other Financing Obligations and Other Credit Facilities (Narrative) (Details) (USD $)	1 Months Ended	3 Months Ended		9 Months Ended
	Jul. 31, 2011	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Line of Credit Facility [Line Items]
Matured credit facility	$ 500,000,000
Debt Instrument principal amount					348,000,000
Loss on debt extinguishment		101,000,000	104,000,000	169,000,000	104,000,000
Cash paid in consideration of senior notes					77,000,000
Amortized cost and debt issuance costs			27,000,000		27,000,000
Refinancing of Revolving Credit Facilities/Repurchase of Senior Notes [Member]
Line of Credit Facility [Line Items]
Repurchase of senior notes				1,000,000,000
Refinancing in revolving credit facilities		3,250,000,000		3,250,000,000
Line of credit facility increased interest rate description				LIBOR plus 2.25 for EPC LIBOR plus 2.00 for EPB LIBPR plus 1.50 to 2.50 for EPEP
Loss on debt extinguishment		(101,000,000)		(169,000,000)
Credit Facilities/Letters of Credit [Member]
Line of Credit Facility [Line Items]
Increase in letter of credit capacity				175,000,000
Weighted average fixed facility fee				1.78%
Debt outstanding under credit facilities		1,300,000,000		1,300,000,000
Letters of Credit and Surety Bonds outstanding		600,000,000		600,000,000
Letter of Credit related to price risk management activities				400,000,000
Total available capacity		1,300,000,000		1,300,000,000
EPPOC [Member]
Line of Credit Facility [Line Items]
Line of credit facility borrowing capacity		750,000,000		750,000,000
Increased revolver capacity on EPPOC from refinancing		1,000,000,000		1,000,000,000
El Paso [Member]
Line of Credit Facility [Line Items]
Line of credit facility borrowing capacity		1,500,000,000		1,500,000,000
Reduced revolver capacity on El Paso facility from refinancing		1,250,000,000		1,250,000,000
Maximum percentage of ownership interest in EPNG or TGP or combination thereof to drop into EPB				100.00%
Ruby Pipeline Financing [Member]
Line of Credit Facility [Line Items]
Financing facility entered for Ruby pipeline project				$ 1,500,000,000