LINES OF CREDIT (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Line of Credit Facility [Line Items]
Total Facility	$ 210,000,000
Usage	65,500,000
Available Liquidity	144,500,000
Average borrowings outstanding during the period	91,400,000	142,400,000
Maximum amounts outstanding during the period	121,900,000	180,500,000
Weighted average borrowing cost	0.37%	0.48%	0.62%
Minimum [Member]
Line of Credit Facility [Line Items]
Financial covenant, ratio of indebtedness to consolidated total capitalization minimum	0.65
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Total Facility	200,000,000
Usage	65,500,000
Available Liquidity	134,500,000
Expiration Date	May 2018
Uncommitted Bank Lines [Member]
Line of Credit Facility [Line Items]
Total Facility	10,000,000
Usage	0
Available Liquidity	10,000,000
Expiration Date	August 2014
South Jersey Gas Commercial Paper Program [Member]
Line of Credit Facility [Line Items]
Total Facility	$ 200,000,000.0
Fixed maturities of notes, at maximum number of days (in days)	270 days