EARNINGS PER SHARE (Details) (USD $) In Thousands, except Share data, unless otherwise specified	0 Months Ended	3 Months Ended
Apr. 09, 2012	Mar. 31, 2013	Mar. 31, 2012
Notes To Consolidated Financial Statements [Abstract]
Net Income Attributable to Controlling Interests		$ 228,089	$ 99,262
Basic		315,129,782	178,055,716
Weighted Average Number Diluted Shares Outstanding Adjustment		872,756	381,737
Diluted		316,002,538	178,437,453
Earnings Per Share Basic And Diluted		$ 0.72	$ 0.56
Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount		6,299	0
Common Stock Issuance Merger With Nstar [Abstract]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares	136,000,000

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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+ Details

- Definition

The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

+ References+ Details

- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

+ References+ Details

- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

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+ Details