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DERIVATIVE INSTRUMENTS - VOLUME (Details) $ in Millions | Jun. 30, 2015 USD ($) Bcf | Jun. 01, 2015 USD ($) | Sep. 30, 2014 Bcf
--- | --- | --- | ---
Derivative [Line Items] |  |  |  |
Notional amount related to treasury lock agreement | $ | $ 125 |  | $ 125 |
NJNG [Member] | Futures [Member] | Long [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, nonmonetary notional amount (in bcf) | 26.2 | [1] |  | 17.3
NJRES [Member] | Futures [Member] | Short [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, nonmonetary notional amount (in bcf) | (57.4) |  |  | (62.1)
NJRES [Member] | Options [Member] | Long [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, nonmonetary notional amount (in bcf) | 1.2 |  |  | 1.2
NJRES [Member] | Physical [Member] | Long [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, nonmonetary notional amount (in bcf) | 58.4 |  |  | 28.6
[1] | Not included is the notional amount of $125 million related to NJNG’s treasury lock agreement.

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