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Energy Consumption Reduction Targets, Cost Recovery, Proposed Return on Equity

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Expenditures for cost recovery program.

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Minimum Energy Requirement to File and Implement A Request For Proposal

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Number of Items Related to the Calculation of Rates

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Number of Requests For Proposal

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Public Utilities, Energy Efficient Reduction Requirement, Percent

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Public Utilities, Long-term Improvement Plan, Recovery Period

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Public Utilities, Number of Parties Who Filed A Brief

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Public Utilities, Number of Proposed Efficient Programs

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Public Utilities, Projected Rate Over-Recovery, Amount

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Public Utilities, Requested Rate Increase Actual Under-Recovery Balance, Amount

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Public Utilities, Requested Reinvestment of Consolidated Tax Adjustment, Percentage

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Public Utility, Capacity Shortfall

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Regulatory matters.

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Request for Proposal, Project Term

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

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

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Regulatory Matters - Pennsylvania and West Virginia (Details) $ in Thousands											6 Months Ended	9 Months Ended	12 Months Ended
	Oct. 14, 2016 USD ($) item brief	Sep. 28, 2016 USD ($)	Aug. 22, 2016 USD ($)	Aug. 16, 2016 USD ($)	Aug. 05, 2016 MW	Jul. 07, 2016	Apr. 28, 2016 USD ($)	Oct. 19, 2015 USD ($)	Jun. 19, 2015	Oct. 10, 2013 proposal	Jun. 30, 2016 USD ($)	Sep. 30, 2016 USD ($) program	Dec. 31, 2017 USD ($)	Dec. 31, 2027 MW	Dec. 31, 2020 MW
Pennsylvania
Regulatory Matters [Line Items]
Number of requests for proposal \| proposal										1
Request for proposal project term										2 years
Pennsylvania \| Unfavorable Regulatory Action
Regulatory Matters [Line Items]
Maximum range of possible loss												$ 175,000
Pennsylvania \| Three month period
Regulatory Matters [Line Items]
Term of energy contract										3 months
Pennsylvania \| Twelve month period
Regulatory Matters [Line Items]
Term of energy contract										12 months
Pennsylvania \| Twenty-four month period
Regulatory Matters [Line Items]
Term of energy contract										24 months
Pennsylvania \| PPUC
Regulatory Matters [Line Items]
LTIIP recovery period								5 years
Pennsylvania \| Pennsylvania Companies
Regulatory Matters [Line Items]
Requested reinvestment of CTA (percent)						50.00%
Pennsylvania \| Pennsylvania Companies \| Subsequent Event
Regulatory Matters [Line Items]
Number of items related to the calculation of rates \| item	1
Number of parties who filed a brief \| brief	2
Pennsylvania \| ME
Regulatory Matters [Line Items]
Amount of requested rate increase (decrease)							$ 140,200
Pennsylvania \| ME \| Subsequent Event
Regulatory Matters [Line Items]
Amount of rate increase waiting approval	$ 96,000
Pennsylvania \| ME \| PPUC
Regulatory Matters [Line Items]
Demand reduction targets proposed return on equity (percent)									1.80%
Energy consumption reduction targets proposed return on equity (percent)									4.00%
Amount of requested rate increase (decrease)								$ 43,440
Pennsylvania \| Penn
Regulatory Matters [Line Items]
Amount of requested rate increase (decrease)							42,000
Pennsylvania \| Penn \| Subsequent Event
Regulatory Matters [Line Items]
Amount of rate increase waiting approval	29,000
Pennsylvania \| Penn \| PPUC
Regulatory Matters [Line Items]
Demand reduction targets proposed return on equity (percent)									1.70%
Energy consumption reduction targets proposed return on equity (percent)									3.30%
Amount of requested rate increase (decrease)								56,350
Pennsylvania \| WP
Regulatory Matters [Line Items]
Amount of requested rate increase (decrease)							98,200
Pennsylvania \| WP \| Subsequent Event
Regulatory Matters [Line Items]
Amount of rate increase waiting approval	66,000
Pennsylvania \| WP \| PPUC
Regulatory Matters [Line Items]
Demand reduction targets proposed return on equity (percent)									1.80%
Energy consumption reduction targets proposed return on equity (percent)									2.60%
Amount of requested rate increase (decrease)								88,340
Pennsylvania \| PN
Regulatory Matters [Line Items]
Amount of requested rate increase (decrease)							$ 158,800
Pennsylvania \| PN \| Subsequent Event
Regulatory Matters [Line Items]
Amount of rate increase waiting approval	$ 100,000
Pennsylvania \| PN \| PPUC
Regulatory Matters [Line Items]
Demand reduction targets proposed return on equity (percent)									0.00%
Energy consumption reduction targets proposed return on equity (percent)									3.90%
Amount of requested rate increase (decrease)								$ 56,740
West Virginia \| MP and PE \| WVPSC
Regulatory Matters [Line Items]
Energy efficient reduction requirement (percent)												0.50%
Expenditures for cost recovery program												$ 10,400
Minimum energy requirement to file and implement a request for proposal \| MW					100
Actual under-recovery balance											$ 119,000
Number of proposed efficient programs \| program												3
West Virginia \| MP and PE \| WVPSC \| ENEC
Regulatory Matters [Line Items]
Amount of requested rate increase (decrease)				$ 65,000
Amount of requested rate increase (percent)				4.70%
West Virginia \| MP and PE \| WVPSC \| Modernization and Improvement Plan for Coal-Fired Boilers
Regulatory Matters [Line Items]
Amount of requested rate increase (decrease)			$ 6,900
Amount of requested rate increase (percent)			0.50%
West Virginia \| MP and PE \| WVPSC \| Accelerated Recovery Costs For Modernizing and Improving Coal-Fired Boilers
Regulatory Matters [Line Items]
Amount of requested rate increase (decrease)		$ 7,400
Scenario, Forecast \| West Virginia \| MP and PE \| WVPSC \| ENEC
Regulatory Matters [Line Items]
Projected rate over-recovery													$ 54,000
Scenario, Forecast \| West Virginia \| MP and PE \| WVPSC \| Accelerated Recovery Costs For Modernizing and Improving Coal-Fired Boilers
Regulatory Matters [Line Items]
Public Utility, Capacity Shortfall \| MW															700
Scenario, Forecast \| West Virginia \| MP \| WVPSC \| IRP
Regulatory Matters [Line Items]
Public Utility, Capacity Shortfall \| MW														850