RATES AND REGULATORY ACTIONS (Details) - USD ($)			1 Months Ended					12 Months Ended
	Oct. 01, 2016	Feb. 29, 2016	Sep. 30, 2016	Jun. 30, 2016	Apr. 30, 2016	Jan. 31, 2016	Oct. 31, 2015	Jun. 30, 2016
Storm Hardening and Reliability Program | Building
Schedule of Capitalization [Line Items]
Roll-in of investments								$ 33,700,000
New Jersey Board of Public Utilities
Schedule of Capitalization [Line Items]
Approved revenue increase (decrease)			$ (600,000)
Universal Service Fund			56,000,000.0
New Jersey Board of Public Utilities | Subsequent event
Schedule of Capitalization [Line Items]
Increase (decrease) in Universal Service Fund	$ 1,100,000
New Jersey Board of Public Utilities | New Jersey
Schedule of Capitalization [Line Items]
Universal Service Fund			5,600,000
New Jersey Board of Public Utilities | Transportation Initiation Clause
Schedule of Capitalization [Line Items]
Approved revenue increase (decrease)					$ 5,200,000
New Jersey Board of Public Utilities | Clean Energy Program
Schedule of Capitalization [Line Items]
Approved revenue increase (decrease)					(7,100,000)
New Jersey Board of Public Utilities | Tenants in Common
Schedule of Capitalization [Line Items]
Approved revenue increase (decrease)					(700,000)
New Jersey Board of Public Utilities | Storm Hardening and Reliability Program
Schedule of Capitalization [Line Items]
Approved revenue increase (decrease)			3,900,000
New Jersey Board of Public Utilities | Conservation Incentive Program
Schedule of Capitalization [Line Items]
Approved revenue increase (decrease)			46,500,000
Energy Efficiency Tracker
Schedule of Capitalization [Line Items]
Increase (decrease) in amount of regulatory costs approved		$ (7,900,000)
Requested revenue increase (decrease)				$ (800,000)
Energy Efficiency Tracker | New Jersey Board of Public Utilities
Schedule of Capitalization [Line Items]
Requested revenue increase (decrease)			(1,600,000)
Basic Gas Supply Service
Schedule of Capitalization [Line Items]
Credits to customers						$ 20,000,000
Approved rate reduction							10.30%
Basic Gas Supply Service | New Jersey Board of Public Utilities
Schedule of Capitalization [Line Items]
Approved revenue increase (decrease)			$ (47,100,000)
Accelerated Infrastructure Replacement Program
Schedule of Capitalization [Line Items]
Extension period of AIRP		7 years
Total amount of investment requested for approval		$ 500,000,000
Total amount of investment request for approval through the end of 2016		$ 76,000,000
Societal Benefits Clause
Schedule of Capitalization [Line Items]
Approved revenue increase (decrease)					$ (2,600,000)