DERIVATIVE INSTRUMENTS - VOLUME (Details) certificate in Thousands, $ in Millions	Mar. 31, 2019 USD ($) Bcf certificate	Sep. 30, 2018 Bcf
Foreign currency contracts
Derivative [Line Items]
Derivative, notional amount \| $	$ 4.3
Natural Gas Distribution \| Long \| Futures
Derivative [Line Items]
Outsanding long (short) derivatives, Volume	(32.1)	(27.9)
Natural Gas Distribution \| Long \| Physical
Derivative [Line Items]
Outsanding long (short) derivatives, Volume	(23.6)	(23.1)
Energy Services \| Physical commodity contracts
Derivative [Line Items]
Number of SRECs \| certificate	(932)
Energy Services \| Long \| Physical
Derivative [Line Items]
Outsanding long (short) derivatives, Volume	(18.6)	(51.2)
Energy Services \| Short \| Futures
Derivative [Line Items]
Outsanding long (short) derivatives, Volume	(4.0)	(7.0)
Energy Services \| Short \| Swaps
Derivative [Line Items]
Outsanding long (short) derivatives, Volume	(8.5)	(17.3)

- Definition

Aggregate notional amount of derivative expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

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- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

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- Definition

Number of Solar Renewable Energy Certificates

+ References

No definition available.

+ Details

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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.

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