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DERIVATIVE INSTRUMENTS - VOLUME (Details) $ in Millions | Dec. 31, 2015 USD ($) Bcf | Sep. 30, 2015 USD ($) Bcf | Jun. 01, 2015 USD ($)
--- | --- | --- | ---
Derivative [Line Items] |  |  |  |
Notional amount | $ |  |  |  | $ 125
Treasury Lock [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Notional amount | $ |  | $ 125 | $ 125 |
NJNG [Member] | Futures [Member] | Long [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Volume (Bcf) | [1] | 19.5 | 25.8 |
NJRES [Member] | Futures [Member] | Short [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Volume (Bcf) |  | (120.8) | (91.1) |
NJRES [Member] | Options [Member] | Long [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Volume (Bcf) |  | 5.8 | 1.2 |
NJRES [Member] | Physical [Member] | Long [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Volume (Bcf) |  | 111.7 | 48.2 |
[1] | Not included is the notional amount of $125 million related to NJNG’s treasury lock agreement.

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