Aggregate notional amount of derivative expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12

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- Definition

Monetary amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12

+ Details

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- Definition

Amount of swap ineffectiveness

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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 45
-Subparagraph b(2)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6887037&loc=d3e80748-113994

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- Definition

The reference rate for the variable rate of the interest rate derivative, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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- Definition

Fixed interest rate related to the interest rate derivative.

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- Definition

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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- Definition

The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5624258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44D
-Subparagraph b
-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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Derivative Instrument and Hedging Activities 1 Narrative (Details) (USD $)		0 Months Ended	6 Months Ended				6 Months Ended						6 Months Ended
	Jun. 30, 2010	Nov. 01, 2011 Interest Rate Swaps [Member]	Jun. 30, 2011 Interest Rate Swaps [Member]	Jun. 30, 2011 Interest Rate Swaps [Member] Ten Year [Member]	Jun. 30, 2011 Interest Rate Swaps [Member] Five Year [Member]	Jun. 30, 2011 Interest Rate Swaps [Member] LNG Holdings [Member]	Jun. 30, 2011 Treasury Rate Locks [Member]	Jun. 30, 2011 Natural Gas Price Swaps [Member] Gathering And Processing [Member]	Jun. 30, 2011 Natural Gas Price Swaps [Member] Gathering And Processing [Member] Year 2011 [Member] MMBtu	Jun. 30, 2011 Natural Gas Price Swaps [Member] Gathering And Processing [Member] Year 2012 [Member] MMBtu	Jun. 30, 2011 Natural Gas Price Swaps [Member] Distribution [Member] Year 2011 [Member] MMBtu	Jun. 30, 2011 Natural Gas Price Swaps [Member] Distribution [Member] Year 2013 [Member] MMBtu	Jun. 30, 2011 NGL Price Swaps [Member] Gathering And Processing [Member]	Jun. 30, 2011 NGL Price Swaps [Member] Gathering And Processing [Member] MMBtus [Member] MMBtu	Jun. 30, 2011 NGL Price Swaps [Member] Gathering And Processing [Member] Gallons [Member] Gallons	Jun. 30, 2011 NGL Price Swaps [Member] Distribution [Member] Year 2012 [Member] MMBtu	Jun. 30, 2011 NGL Processing Spread Swaps [Member] Gathering And Processing [Member] MMBtu
Derivative Line Items
Derivative Notional Amount			$ 525,000,000	$ 450,000,000	$ 75,000,000	$ 455,000,000
Derivative Description Of Variable Rate Basis		three-month LIBOR plus a credit spread of 3.0175 percent
Derivative Ineffectiveness			no swap ineffectiveness
Derivative Fixed Interest Rate			3.63%
Cash Flow Hedge Gain Loss To Be Reclassified Within Twelve Months			14,200,000				571,000	6,000,000					1,600,000
Derivative Nonmonetary Notional Amount									8,280,000	3,660,000	8,490,000	2,020,000		5,490,000	65,378,124	14,270,000	4,600,000
Derivative Net Liability Position Aggregate Fair Value	$ 8,000,000