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DERIVATIVE INSTRUMENTS, VOLUME (Details) $ in Millions | Sep. 30, 2015 USD ($) Bcf | Jun. 01, 2015 USD ($) | Sep. 30, 2014 Bcf
--- | --- | --- | ---
Derivative [Line Items] |  |  |  |
Notional amount | $ |  |  | $ 125 |
Treasury Lock [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Notional amount | $ | $ 125 |  |  |
NJNG [Member] | Futures [Member] | Long Position [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Outstanding long (short) derivatives (in Bcf) | 25.8 | [1] |  | 17.3
NJRES [Member] | Futures [Member] | Short Position [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Outstanding long (short) derivatives (in Bcf) | (91.1) |  |  | (62.1)
NJRES [Member] | Financial Options [Member] | Long Position [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Outstanding long (short) derivatives (in Bcf) | 1.2 |  |  | 1.2
NJRES [Member] | Physical [Member] | Long Position [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Outstanding long (short) derivatives (in Bcf) | 48.2 |  |  | 28.6
[1] | Not included is the notional amount of $125 million related to NJNG’s treasury lock agreement.

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