SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Significant Accounting Policies [Line Items]
Treasury Stock Acquired, Repurchase Authorization	$ 20ogs_TreasuryStockAnnualAuthorizedAmount
Common stock, shares authorized	250,000,000us-gaap_CommonStockSharesAuthorized		250,000,000us-gaap_CommonStockSharesAuthorized
Number of natural gas distribution services customers	2,000,000
Segment Reporting, Disclosure of Major Customers	0	0

Number of customers the natural gas distribution service segment services.

No definition available.

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- Details

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- Definition

The annual authorized limit of treasury stock purchases, exclusive of funds received through the dividend reinvestment and employee stock purchase plans.

+ References

No definition available.

+ Details

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

+ Details

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- Definition

Disclosure of the extent of enterprise reliance on its major customers. For example, includes revenues from transactions with a single external customer amounting to 10 percent or more of the entity's revenues, the total amount of revenues from each such customer, and the identity of the segment or segments reporting the revenues. A group of entities that the entity knows to be under common control generally will be considered a single customer for inclusion in this item. The federal government, a state government, a local government (for example, a county or municipality), or a foreign government each will generally be considered as a single customer for inclusion in this item.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 280

-SubTopic 10

-Section 50

-Paragraph 42

-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e9054-108599

+ Details

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