Commitments And Contingencies (Details) $ in Millions	9 Months Ended
Jun. 30, 2018 USD ($)
Site Contingency [Line Items]
Estimated minimum liability for environmental remediation	$ 7.7
Rate recovery period	4 years
Project Costs	$ 75.6
Former Manufactured Gas Plant Site New York [Member]
Site Contingency [Line Items]
Estimated minimum liability for environmental remediation	$ 4.2

Project costs included within Property, Plant and Equipment and Deferred Charges on the Consolidated Balance Sheet.

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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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Remaining recovery period of regulatory assets for which no return on investment during recovery period is provided, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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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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