RELATED PARTY TRANSACTIONS	12 Months Ended
RELATED PARTY TRANSACTIONS	Sep. 30, 2011
Related Party Transactions [Abstract]
Related Party Transactions Disclosure [Text Block]	RELATED PARTY TRANSACTIONS NJRES may periodically enter into storage, or park and loan agreements with its affiliated FERC-regulated natural gas storage facility, Steckman Ridge, or transportation agreements with its affiliated FERC-regulated interstate pipeline, Iroquois Gas Transmission. As of September 30, 2011, NJRES has entered into storage and park and loan transactions with Steckman Ridge for varying terms, all of which expire by October 2012. Additionally, NJRES and NJNG both have transportation capacity with Iroquois Gas Transmission that expires by March 2019 and January 2019, respectively. Demand fees expensed for Steckman Ridge and Iroquois Gas Transmission were $5.6 million during the fiscal year ended September 30, 2011. As of September 30, 2011, NJRES had fees payable of $237,000 and $389,000 to Steckman Ridge and Iroquois Gas Transmission, respectively. In January 2010, NJNG entered into a ten-year agreement effective April 1, 2010 through March 31, 2020, for 3 Bcf of firm storage capacity with Steckman Ridge. Under the terms of the agreement, NJNG incurs demand fees, at market rates, of approximately $9.3 million annually. These fees are recoverable through NJNG's BGSS mechanism. Demand fees incurred during fiscal September 30, 2011 were $9.3 million. As of September 30, 2011, NJNG had fees payable to Steckman Ridge in the amount of $775,000. In December 2009, NJNG and NJRES entered into an asset management agreement that began in January 2010 and ends in March 2013. Under the terms of this agreement, NJNG released certain transportation and storage contracts to NJRES for the entire term of the agreement. NJNG also sold approximately 1 Bcf of natural gas in storage at cost to NJRES. In return, NJNG has the option to purchase index priced gas from NJRES at NJNG's city gate and other delivery locations to maintain operational reliability. In September 2010, NJNG and NJRES entered into an another asset management agreement that began in September 2010 and ends October 2014, whereby NJNG released additional transportation contracts to NJRES for the entire term of the agreement and has the option to purchase index priced gas from NJRES at NJNG's city gate.

The entire disclosure for related party transactions, including the nature of the relationship(s), a description of the transactions, the amount of the transactions, the effects of any change in the method of establishing the terms of the transaction from the previous period, stated interest rate, expiration date, terms and manner of settlement per the agreement with the related party, and amounts due to or from related parties. If the entity and one or more other entities are under common ownership or management control and this control affects the operating results or financial position, disclosure includes the nature of the control relationship even if there are no transactions between the entities. Disclosure may also include the aggregate amount of current and deferred tax expense for each statement of earnings presented where the entity is a member of a group that files a consolidated tax return, the amount of any tax related balances due to or from affiliates as of the date of each statement of financial position presented, the principal provisions of the method by which the consolidated amount of current and deferred tax expense is allocated to the members of the group and the nature and effect of any changes in that method. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

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