SUPPLEMENTAL INFORMATION (Details) (USD $)	0 Months Ended		3 Months Ended
	Mar. 08, 2014	Mar. 06, 2014 plant	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Operating Leased Assets [Line Items]
Cash paid for interest, net of amounts capitalized			$ 2,776,000	$ 2,478,000
Cash paid for taxes, net of refunds received			23,000
Accounts payable related to capital expenditures			1,628,000	22,996,000
Change in value recognized in other comprehensive income			11,000	69,000
Capital lease obligation			307,000	0
Accrued distribution equivalent rights (DERs) on the LTIP units			76,000	21,000
Interest Costs Incurred [Abstract]
Total interest costs			3,072,000	2,649,000
Capitalized interest included in property, plant and equipment, net			(99,000)	(602,000)
Interest expense			2,973,000	2,047,000
Deferred Financing Costs [Roll Forward]
Deferred financing costs, January 1			5,056,000		5,237,000
Capitalization of deferred financing costs			156,000
Amortization of deferred financing costs			(337,000)	(267,000)
Deferred financing costs, March 31			5,056,000		5,237,000
Number of power plants		2	2
Contractual agreement, term	10 years	10 years
Contingent fees			200,000
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability			100,000
Natural Gas Pipeline Contracts [Member]
Deferred Financing Costs [Roll Forward]
Operating leases, future minimum payments due, remainder of current year			3,700,000
Operating leases, future minimum payments due in second year			5,600,000
Operating leases, future minimum payments due in third year			5,600,000
Operating leases, future minimum payments due in fourth year			5,600,000
Operating leases, future minimum payments due in fifth year			2,200,000
Operating leases, future minimum payments due in sixth year			2,200,000
Operating leases, future minimum payments due after sixth year			$ 15,300,000