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Maximum Period Post Petition to File General Rate Filing

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Public Utilities, Reclassification of Project Costs Expensed in Prior Periods

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The carrying amount of deferred costs.

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

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Amount before accumulated depreciation, depletion and amortization of other physical assets used in the normal conduct of business to produce goods and services and not intended for resale.

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Amount of public utility's interim rate increase (decrease) allowed while waiting final decision of regulatory agency.

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Amount of public utility's requested rate increase (decrease) with regulatory agency.

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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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Remaining balance of regulatory assets for which no return on investment during recovery is provided. In some cases, a regulator may permit an enterprise to include a cost that would be charged to expense by an unregulated enterprise as an allowable cost over a period of time by amortizing that cost for rate-making purposes, but the regulator does not include the unrecovered amount in the rate base.

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Regulatory Assets and Liabilities and Regulatory Matters (Details) - USD ($) $ in Thousands					1 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended
	Jun. 30, 2016	Apr. 01, 2016	Jan. 19, 2016	Apr. 01, 2015	Mar. 31, 2016	Mar. 31, 2016	Jun. 30, 2016	Sep. 30, 2014	Sep. 30, 2015	Jun. 30, 2015
Regulatory Assets
Capitalized project costs					$ 5,830	$ 5,830
Project costs expensed in prior periods						5,375
Pennsylvania Public Utility Commission
Regulatory Assets
Requested operating revenue increase			$ 58,600
Operating revenue increase	$ 27,000
Maximum period post petition to file general rate filing (in years)							5 years
Pennsylvania Public Utility Commission \| Maximum
Regulatory Assets
Distribution system improvement charge, percent of amount billed to customers					5.00%		5.00%	0.00%
Pennsylvania Public Utility Commission \| Maximum \| PNG
Regulatory Assets
Distribution system improvement charge, percent of amount billed to customers				0.00%	10.00%
Pennsylvania Public Utility Commission \| Maximum \| CPG
Regulatory Assets
Distribution system improvement charge, percent of amount billed to customers		0.00%			10.00%
Technology Equipment
Regulatory Assets
Associated increases to utility property, plant and equipment					$ 2,755	2,755
Gas Utility
Regulatory Assets
Fair value of unrealized gains (losses)	$ 5,483						$ 5,483		$ (3,262)	$ (729)
Electric Utility
Regulatory Assets
Fair value of unrealized gains (losses)									$ (533)	$ (1,428)
Deferred Project Costs
Regulatory Assets
Associated increases to utility regulatory assets					$ 3,075	$ 3,075