ACQUISITIONS (Revenue and Net Income) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Business Acquisition [Line Items]
Revenues	$ 59,285	$ 40,107	$ 110,411	$ 75,890
Net income	7,533	9,129	20,600	16,716
Summit Midstream Partners, LP
Business Acquisition [Line Items]
Revenues	43,743		87,338
Net income	7,790		20,270
Bison Midstream, LLC
Business Acquisition [Line Items]
Bison Gas Gathering system revenues	15,542		23,073
Bison Gas Gathering system net (loss) income	$ (257)		$ 330

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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+ Details