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DERIVATIVE INSTRUMENTS - BROKER MARGIN DEPOSITS (Details) - USD ($) $ in Thousands | Mar. 31, 2017 | Sep. 30, 2016
--- | --- | ---
NJNG |  |
Derivative [Line Items] |  |
Broker margin - Current assets | $ 3,354 | $ 4,822
NJRES |  |
Derivative [Line Items] |  |
Broker margin - Current assets | $ 20,250 | $ 42,822

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of other receivables due from broker-dealers or clearing organizations. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
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Balance Type: | debit
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- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |

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- Details
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Balance Type: |
Period Type: |