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Cost of emission control equipment installed

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- Definition

Time frame emission control equipment

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Potential percentage of recovery.

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Number of recovery units potentially affected by National Ambient Air Quality Standards.

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The amount of expense provided in the period for legal costs incurred on or before the balance sheet date pertaining to resolved, pending or threatened litigation, including arbitration and mediation proceedings.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 5

-Paragraph 9

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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-Name Accounting Standards Codification

-Topic 225

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-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.3)

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Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6952336&loc=d3e14326-108349

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

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-Name Accounting Standards Codification

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-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.25)

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Best estimate of the loss exposure for reasonably possible environmental contingencies at an individual site for which no accrual has been recorded.

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

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 96-1

-Paragraph 163

-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 FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 30

-Section 50

-Paragraph 10

-Subparagraph (c),(d)(2)

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Commitments and Contingencies 2 Narrative (Details) (USD $)	0 Months Ended	9 Months Ended
	Jul. 07, 2011	Sep. 30, 2011	Dec. 31, 2010
Commitments And Contingencies [Abstract]
Legal Fees	$ 18,500,000
Percentage Of Recovery	50
Estimated Litigation Liability		28,100,000	26,900,000
Recovery Units		three
Southern Union Gas Services [Member]
Commitments And Contingencies [Abstract]
Site Contingency Loss Exposure Not Accrued Best Estimate		518,720
Alleged Violations		19
Emission Control Equipment		50,000,000
Emission Control Equipment Years		nine
North Attleboro Site [Member]
Commitments And Contingencies [Abstract]
Site Contingency Loss Exposure Not Accrued Best Estimate		$ 10,900,000