Energy Contract, Term

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- Definition

Number of Requests For Proposal

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- Definition

Public Utilities, Approved Maintenance Cycle

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- Definition

Public Utilities, Cost Recovery Period

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- Definition

Public Utilities, Property, Plant and Equipment, Proposed Potential Plant Disposal Capacity

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- Definition

Regulatory matters.

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- Definition

Request for Proposal, Project Term

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- Definition

Amount of public utility's approved rate increase (decrease) by regulatory agency.

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- Definition

Percentage of public utility's approved return on equity.

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- Definition

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

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- Definition

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

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- Definition

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

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Regulatory Matters - Pennsylvania and West Virginia (Details) $ in Millions					1 Months Ended	3 Months Ended	12 Months Ended
	Mar. 12, 2020	Mar. 11, 2020	Aug. 30, 2019 USD ($)	Aug. 21, 2019 USD ($)	Mar. 31, 2016 USD ($)	Mar. 31, 2020 proposal	Dec. 31, 2019	Oct. 11, 2019 MW
Pennsylvania \| DSP June 2019- May 2023
Regulatory Matters [Line Items]
Number of RFP's \| proposal						2
RFP term						2 years
Pennsylvania \| Three Month Period \| DSP June 2019- May 2023
Regulatory Matters [Line Items]
Term of energy contract						3 months
Pennsylvania \| Twelve month period \| DSP June 2019- May 2023
Regulatory Matters [Line Items]
Term of energy contract						12 months
Pennsylvania \| Twenty-four month period \| DSP June 2019- May 2023
Regulatory Matters [Line Items]
Term of energy contract						24 months
Pennsylvania \| Pennsylvania Companies \| PPUC \| EE&C Phase III
Regulatory Matters [Line Items]
Approved amount of annual increase					$ 390.0
Pennsylvania \| Pennsylvania Companies \| PPUC \| New LTIIPs
Regulatory Matters [Line Items]
Amount of requested rate increase (decrease)			$ 572.0
Recovery period			5 years
Pennsylvania \| Pennsylvania Companies \| PPUC \| Wavier of DSIC Cap
Regulatory Matters [Line Items]
Amount of requested rate increase (decrease) (percent)			11.81%
Approved ROE		5.00%
Temporary increase in rate cap	7.50%
West Virginia \| MP and PE \| WVPSC \| ENEC
Regulatory Matters [Line Items]
Amount of requested rate increase (decrease)				$ (6.1)
Amount of requested rate increase (decrease) (percent)				(0.40%)
West Virginia \| MP and PE \| WVPSC \| Termination Agreement of PURPA Power Purchase Agreement
Regulatory Matters [Line Items]
Proposed plant disposal capacity (in MW's) \| MW								50
West Virginia \| MP and PE \| WVPSC \| VMS
Regulatory Matters [Line Items]
Amount of requested rate increase (decrease)				$ 7.6
Amount of requested rate increase (decrease) (percent)				0.05%
Maintenance cycle						5 years	4 years