RELATED PARTY TRANSACTIONS (Details) (USD $)	3 Months Ended	9 Months Ended
	Jun. 30, 2012	Jun. 30, 2012
NJRES to Steckman Ridge Affiliate
Related Party Transaction [Line Items]
Demand Fees Expense Recognized Pertaining to Related Party Agreement	$ 1,800,000	$ 6,000,000
Due to Related Parties	170,000	170,000
NJRES to Iroquois Affiliate [Member]
Related Party Transaction [Line Items]
Due to Related Parties	395,000	395,000
NJNG to NJRES Affilate [Member]
Related Party Transaction [Line Items]
Natural Gas Sold at Cost Under Asset Management Agreement (MMcf)		1,000
NJNG to Steckman RIdge Affiliate
Related Party Transaction [Line Items]
Demand Fees Expense Recognized Pertaining to Related Party Agreement	2,500,000	6,500,000
Agreement for Natural Gas Storage Capacity Between NJNG and Affiliate (MMcf)		3,000
Approximate Annual Demand Fees Under Agreement from April 1 2010 to March 31 2020		9,300,000
Due to Related Parties	775,000	775,000
NJNG to Iroquois Affiliate [Member]
Related Party Transaction [Line Items]
Due to Related Parties	$ 61,000	$ 61,000