v2.4.0.8

Accumulated Other Comprehensive Loss (Narrative) (Details) (Millennium Pipeline Company, L.L.C [Member])	6 Months Ended
	Jun. 30, 2013
Millennium Pipeline Company, L.L.C [Member]
Accumulated Other Comprehensive Loss [Line Items]
Debt instrument maturity date	Jun. 01, 2025

X

- Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ 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)(2))

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

+ Details

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