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

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

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- Definition

Derivative, Notional Amount, Period Of Forecasted Interest Payments Covered By Unsettled Hedges

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- Definition

Maximum length of time hedged in price risk cash flow hedges.

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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.

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- Definition

Nominal energy measure used to calculate payments on a derivative instrument.

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- Definition

The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

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The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. For a classified balance sheet represents the current portion only (the noncurrent portion has a separate concept); there is a separate and distinct element for unclassified presentations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.1)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Derivative Instruments and Hedging Activities (Details) kWh in Millions, MMBTU in Millions		12 Months Ended
	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) MMBTU kWh	Sep. 30, 2014 USD ($) MMBTU kWh
Derivative
Interest rate cash flow hedge loss to be reclassified during next 12 months, net		$ 2,463,000
Restricted cash in brokerage accounts	$ 3,592,000	$ 6,602,000	$ 3,592,000
Gas Utility
Derivative
Maximum length of time hedged in price risk cash flow hedges (in months)	12 months
Notional amount (in units) \| MMBTU		18.9	16.9
Electric Utility
Derivative
Maximum length of time hedged in price risk cash flow hedges (in months)	8 months
Notional amount (in units) \| kWh		331.0	237.0
Electric Utility \| Electric Utility Electric Transmission Congestion
Derivative
Maximum length of time hedged in price risk cash flow hedges (in months)	8 months
Notional amount (in units) \| kWh		277.1	232.1
Interest Rate Protection Agreements
Derivative
Underlying variable rate debt	$ 0	$ 250,000,000,000	$ 0
Minimum \| Interest Rate Protection Agreements
Derivative
Duration of forecasted interest payments covered by unsettled hedges (in years)		10 years
Maximum \| Interest Rate Protection Agreements
Derivative
Duration of forecasted interest payments covered by unsettled hedges (in years)		30 years