v2.4.0.6

Commitments and Contingencies - Narrative (Details) (USD $)			3 Months Ended
	Mar. 31, 2013	Mar. 31, 2013 Regency 4.50% Senior Notes Due 2023 [Member]	Mar. 31, 2013 North Attleboro Site [Member]	Mar. 31, 2013 Attorney General of Commonwealth [Member]	Mar. 31, 2013 Mercury Release [Member]	Sep. 30, 2012 Mercury Release [Member]	Dec. 31, 2009 Mercury Release [Member]	Mar. 31, 2013 Accrued Liabilities [Member]	Dec. 31, 2012 Accrued Liabilities [Member]
Commitments And Contingencies [Line Items]
Guarantor Obligations, Current Carrying Value	$ 600,000,000
Debt Instrument, Interest Rate, Stated Percentage		4.50%
Estimated remediation costs to completion			11,000,000
Legal fees				19,000,000
Level of recovery				50.00%
Reimbursed expert and consultant costs, maximum				150,000
Estimated cost							6,000,000
Community Service Obligation							12,000,000
Original Fine Amount						50,000
Fine Amount Sought						500,000
Accrued liabilities, litigation and other claim-related					$ 500,000			$ 27,000,000	$ 27,000,000

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- Definition

Dollar value of community service portion of a fine imposed in connection with a contingent obligation.

+ References

No definition available.

+ Details

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- Definition

Proposed penalties associated with alleged violations.

+ References

No definition available.

+ Details

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- Definition

Amount of fine that would be imposed in connection with a contingent obligation, based on proposed alternative structure.

+ References

No definition available.

+ Details

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- Definition

Amount of fine associated with a contingent obligation, as originially imposed.

+ References

No definition available.

+ Details

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- Definition

Potential portion of refund to costomers in connection with a regulatory complaint.

+ References

No definition available.

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- Definition

Maximum amount of costs to be reimbursed by the company in connection with a regulatory complaint.

+ References

No definition available.

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- Definition

Interest rate stated in the contractual debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ 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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

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-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 45

-Paragraph 13

-Subparagraph c

-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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- Definition

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

+ Details

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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.25)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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

+ References

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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 30

-Section 50

-Paragraph 10

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

-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13237-110859

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