DERIVATIVE INSTRUMENTS (Details) MWh in Millions	12 Months Ended
	Dec. 31, 2015 USD ($) MWh		Dec. 31, 2015 USD ($) MMcfe
Marina Energy LLC [Member] | Interest Rate Swap, 14,500,000 [Member]
Derivative [Line Items]
Notional Amount	$ 14,500,000		$ 14,500,000
Fixed Interest Rate	3.905%		3.905%
Marina Energy LLC [Member] | Interest Rate Swap, 500,000 [Member]
Derivative [Line Items]
Notional Amount	$ 500,000		$ 500,000
Fixed Interest Rate	3.905%		3.905%
Marina Energy LLC [Member] | Interest Rate Swap, 330,000 [Member]
Derivative [Line Items]
Notional Amount	$ 330,000		$ 330,000
Fixed Interest Rate	3.905%		3.905%
Marina Energy LLC [Member] | Interest Rate Swap, 7,100,000 [Member]
Derivative [Line Items]
Notional Amount	$ 7,100,000	[1]	$ 7,100,000	[1]
Fixed Interest Rate	4.895%	[1]	4.895%	[1]
South Jersey Gas Company [Member] | Interest Rate Swap, 12,500,000 Contract 1 [Member]
Derivative [Line Items]
Notional Amount	$ 12,500,000		$ 12,500,000
Fixed Interest Rate	3.43%		3.43%
South Jersey Gas Company [Member] | Interest Rate Swap, 12,500,000 Contract 2 [Member]
Derivative [Line Items]
Notional Amount	$ 12,500,000		$ 12,500,000
Fixed Interest Rate	3.43%		3.43%
Basis and index related purchase and sales contracts [Member]
Derivative [Line Items]
Notional amount, energy | MMcfe			179,000
Purchase transaction [Member]
Derivative [Line Items]
Notional amount, energy	3.2		82,100
Sale transaction [Member]
Derivative [Line Items]
Notional amount, energy	3.0		70,100

[1] The Company currently does not have any plans to renew this interest rate swap.