IDENTIFIABLE INTANGIBLE ASSETS, NONCURRENT LIABILITY AND GOODWILL (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 562,634		$ 562,634		$ 559,365
Accumulated amortization	(76,555)		(76,555)		(57,188)
Total intangible assets, net	486,079		486,079		502,177
Noncurrent liability
Unfavorable gas gathering contract, useful lives			10 years		10 years
Unfavorable contract, Gross Carrying Amount	10,962		10,962		10,962
Unfavorable gas gathering contract, Accumulated Amortization	(5,007)		(5,007)		(4,588)
Unfavorable gas gathering contract, Net	5,955		5,955		6,374
Amortization expense
Amortization expense - unfavorable contract	211	277	419	569
Amortization of favorable and unfavorable contracts	(225)	(250)	(451)	(530)
Assets
2014	20,589		20,589
2015	43,872		43,872
2016	44,114		44,114
2017	42,846		42,846
2018	43,115		43,115
Liability
2014	806		806
2015	1,650		1,650
2016	1,571		1,571
2017	1,438		1,438
2018	490		490
Favorable gas gathering contract
Finite-Lived Intangible Assets [Line Items]
Useful lives			18 years 8 months 12 days		18 years 8 months 12 days
Gross carrying amount	24,195		24,195		24,195
Accumulated amortization	(7,185)		(7,185)		(6,315)
Total intangible assets, net	17,010		17,010		17,880
Amortization expense
Amortization expense	436	527	870	1,099
Contract intangibles
Finite-Lived Intangible Assets [Line Items]
Useful lives			12 years 6 months		12 years 6 months
Gross carrying amount	426,464		426,464		426,464
Accumulated amortization	(59,318)		(59,318)		(43,158)
Total intangible assets, net	367,146		367,146		383,306
Amortization expense
Amortization expense	8,198	7,421	16,160	12,709
Rights-of-way
Finite-Lived Intangible Assets [Line Items]
Useful lives			24 years 2 months		24 years 4 months
Gross carrying amount	111,975		111,975		108,706
Accumulated amortization	(10,052)		(10,052)		(7,715)
Total intangible assets, net	101,923		101,923		100,991
Amortization expense
Amortization expense	$ 1,178	$ 872	$ 2,337	$ 1,680