LONG-TERM DEBT (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2014 Senior Notes [Member] Series Due Jun 2019, 3.05% [Member]	Jun. 30, 2014 Senior Notes [Member] Series Due June 2019, Floating Rate [Member]	Jun. 30, 2014 South Jersey Gas Company [Member]	Jun. 30, 2014 South Jersey Gas Company [Member] Line of Credit [Member]	Jan. 31, 2014 South Jersey Gas Company [Member] Mortgages [Member] Series Due January 2030, 4.23% [Member]
Debt Instrument [Line Items]
Debt face amount			$ 60,000,000	$ 40,000,000			$ 30,000,000
Stated interest rate	7.50%		3.05%				4.23%
Credit facility borrowing capacity	610,000,000				210,000,000	200,000,000.0
Carrying amount of long-term debt	$ 890,400,000	$ 701,400,000				$ 59,000,000
Floating rate				1.56%