RATES AND REGULATORY ACTIONS (Details) (USD $)	1 Months Ended							24 Months Ended	1 Months Ended			12 Months Ended	276 Months Ended	1 Months Ended
	Sep. 30, 2014	Aug. 31, 2014	Sep. 30, 2013	Jun. 30, 2013	Feb. 28, 2013	Jul. 31, 2012	Sep. 30, 2010	Dec. 31, 2013	Jan. 31, 2010	Jan. 31, 2014	Jan. 31, 2013	Dec. 31, 2014 sites	Dec. 31, 2014 sites	Aug. 31, 2008	Oct. 31, 2013	May 31, 2014	May 31, 2013	Jun. 30, 2012	Oct. 31, 2012	May 31, 2012	Sep. 30, 2012	Jul. 31, 2013	Jan. 31, 2009	Jan. 31, 2015	Jul. 31, 2014	Jun. 30, 2014	Nov. 30, 2012
Schedule of Capitalization [Line Items]
Public Utilities, Approved Base Rate Increase	$ 20,000,000						$ 42,100,000
Public Utilities, Rate of Return on Base Rate	7.10%						8.21%
Public Utilities, Return on Common Equity	9.75%						10.30%
Public Utilities, Annual Depreciation Reduction Attributable To Petition							1,200,000
Investment Requested to be Recovered through CIRT, Investments To Be Rolled to Base Rate								22,500,000							95,000,000
Public Utilities, Depreciate Rate	2.10%							2.40%
Investment Requested to be Recovered through CIRT III, Term of AIRP					4 years	5 years
Investment Requested to be Recovered through CIRT III, Amount of AIRP					141,200,000	250,000,000
Investment Requested to be Recovered through CIRT III, Annual Amount of AIRP					35,300,000
Investment Requested to be Recovered through SHARP		103,500,000	280,000,000
Investment Requested to be Recovered through SHARP, Term		3 years	7 years
Number of sites for environmental cleanup (in sites)												12	12
Regulatory Assets								296,081,000				357,160,000	357,160,000
Regulated Operations, Number of Customers Purchasing Energy Commodities From A Provider Other Then The Reporting Entity (in customers)												38,347	38,347
Costs Requested for Deferral, Storm Related				700,000
Environmental Restoration Costs Expended Net [Member]
Schedule of Capitalization [Line Items]
Regulatory Assets								29,945,000				29,540,000	29,540,000
Other Regulatory Assets, Deferred Pipeline Integrity Costs [Member]
Schedule of Capitalization [Line Items]
Regulatory Assets								2,800,000				3,400,000	3,400,000
Conservation Incentive Program [Member]
Schedule of Capitalization [Line Items]
Public Utilities, Approved Base Rate Increase							16,600,000
Amount of Regulatory Costs Approved																21,800,000	17,800,000
Regulatory Costs, Extension Period									1 year
Amount of Regulatory Costs Not yet Approved, Prior Year Carryover																		28,000,000
Conservation Incentive Program [Member] | Non Weather [Member]
Schedule of Capitalization [Line Items]
Amount of Regulatory Costs Not yet Approved																4,200,000	2,300,000	8,400,000
Conservation Incentive Program [Member] | Weather [Member]
Schedule of Capitalization [Line Items]
Amount of Regulatory Costs Not yet Approved																26,000,000	15,500,000	19,600,000
Capital Investment Recovery Tracker [Member]
Schedule of Capitalization [Line Items]
Public Utilities, Approved Base Rate Increase							6,800,000
Investment Requested to be Recovered through CIRT, Investments To Be Rolled to Base Rate																			110,600,000
Amount of Regulatory Costs Not yet Approved																			13,200,000
Investment Requested to be Recovered through CIRT, Revenue Increase			15,500,000
Capital Investment Recovery Tracker [Member] | Capital Expenditures [Member]
Schedule of Capitalization [Line Items]
Amount of Regulatory Costs Not yet Approved																				35,000,000
Amount of Regulatory Costs Approved							81,300,000
Incremental Revenue [Member]
Schedule of Capitalization [Line Items]
Public Utilities, Approved Base Rate Increase							18,700,000
Accelerated Infrastructure Replacement Program [Member]
Schedule of Capitalization [Line Items]
Public Utilities, Approved Base Rate Increase	7,500,000
Investment Requested to be Recovered through CIRT, Investments To Be Rolled to Base Rate	69,900,000
Basic Gas Supply Service [Member]
Schedule of Capitalization [Line Items]
Amount of Regulatory Costs Not yet Approved																27,000,000		27,000,000
Amount of Regulatory Costs Not yet Approved, Percent Change in Recoveries																9.30%		8.80%
Amount of Regulatory Costs Approved	27,000,000		600,000																		27,000,000
Amount of Regulatory Costs Approved, Percent Change in Recoveries																					8.80%
Proceeds from Refunds From Favorable Regulatory Action										11,200,000	9,400,000
Energy Efficiency Tracker [Member]
Schedule of Capitalization [Line Items]
Amount of Regulatory Costs Not yet Approved																1,400,000	2,200,000	5,800,000		3,100,000
Amount of Regulatory Costs Approved	2,200,000			24,000,000																		2,100,000
Amount of Regulatory Costs Available Under Program																							17,000,000
Energy Efficiency Tracker [Member] | Subsequent Event [Member]
Schedule of Capitalization [Line Items]
Amount of Regulatory Costs Approved, Statewide																								56,000,000
Societal Benefits Clause [Member]
Schedule of Capitalization [Line Items]
Amount of Regulatory Costs Not yet Approved						11,800,000																(6,400,000)			(25,700,000)
Remediation Adjustment Clause [Member]
Schedule of Capitalization [Line Items]
Number of sites for environmental cleanup (in sites)												12	12
Amortization Period of Environmental Remediation Costs (in years)												7 years
Regulated Costs Recovered													106,100,000
Remediation Adjustment Clause [Member] | Environmental Restoration Costs Expended Net [Member]
Schedule of Capitalization [Line Items]
Regulatory Assets								29,900,000				29,500,000	29,500,000
New Jersey Clean Energy Program [Member]
Schedule of Capitalization [Line Items]
Amount of Regulatory Costs Approved, Statewide				345,000,000										1,200,000,000
Regulatory Costs For Which Reporting Entity is Responsible For														41,500,000												14,500,000	7,500,000
Regulatory Costs For Which Reporting Entity is Responsible For, Period of Recovery (in years)														4 years
Universal Service Fund [Member]
Schedule of Capitalization [Line Items]
Amount of Regulatory Costs Approved	7,900,000		5,800,000																		8,200,000
Amount of Regulatory Costs Approved, Statewide	71,800,000		54,400,000																		78,000,000
Amount of Regulatory Costs Not yet Approved, Statewide				(29,400,000)														(500,000)								19,900,000
Amount of Regulatory Costs Not Yet Approved, Annual Revenue Impact				(3,700,000)														(100,000)								2,600,000
Amount of Regulatory Costs Approved, Annual Revenue Impact	$ (2,600,000)		$ 3,400,000																		$ 100,000