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Number of Requests For Proposal

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Regulatory matters.

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

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Percentage 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 Millions						1 Months Ended
	Jan. 17, 2020	Aug. 30, 2019 USD ($)	Aug. 21, 2019 USD ($)	Jun. 01, 2019 proposal MW	May 23, 2019 USD ($)	Mar. 31, 2016 USD ($)	Oct. 11, 2019 MW
Pennsylvania \| ME
Regulatory Matters [Line Items]
Approved amount of rate increase					$ 45.0
Pennsylvania \| Penn
Regulatory Matters [Line Items]
Approved amount of rate increase					26.0
Pennsylvania \| WP
Regulatory Matters [Line Items]
Approved amount of rate increase					51.0
Pennsylvania \| PN
Regulatory Matters [Line Items]
Approved amount of rate increase					$ 25.0
Pennsylvania \| PPUC \| Pennsylvania Companies \| DSP
Regulatory Matters [Line Items]
Number of RFP's \| proposal				2
Project term				2 years
New hourly priced default service threshold (in MW's) \| MW				0.1
Pennsylvania \| PPUC \| Pennsylvania Companies \| DSP \| 3 Month Period
Regulatory Matters [Line Items]
Energy contract term				3 months
Pennsylvania \| PPUC \| Pennsylvania Companies \| DSP \| 12 Month Period
Regulatory Matters [Line Items]
Energy contract term				12 months
Pennsylvania \| PPUC \| Pennsylvania Companies \| DSP \| 24 Month Period
Regulatory Matters [Line Items]
Energy contract term				24 months
Pennsylvania \| PPUC \| Pennsylvania Companies \| EE&C
Regulatory Matters [Line Items]
Approved amount of rate increase						$ 390.0
Pennsylvania \| PPUC \| Pennsylvania Companies \| New LTIP's
Regulatory Matters [Line Items]
Requested rate increase (decrease)		$ 572.0
Pennsylvania \| PPUC \| Pennsylvania Companies \| Wavier of Distribution System Improvement Charge Cap
Regulatory Matters [Line Items]
Requested rate increase (decrease) (percent)		11.81%
West Virginia \| WVPSC \| MP and PE \| ENEC
Regulatory Matters [Line Items]
Requested rate increase (decrease)			$ (6.1)
Requested rate increase (decrease) (percent)			(0.40%)
West Virginia \| WVPSC \| MP and PE \| Termination Agreement of PURPA Power Purchase Agreement
Regulatory Matters [Line Items]
Proposed potential plant disposal capacity (in MW's) \| MW							50
West Virginia \| WVPSC \| MP and PE \| Vegetation Management Surcharge Rates
Regulatory Matters [Line Items]
Requested rate increase (decrease)			$ 7.6
Requested rate increase (decrease) (percent)			0.05%
Subsequent Event \| Pennsylvania \| PPUC \| Pennsylvania Companies \| Wavier of Distribution System Improvement Charge Cap
Regulatory Matters [Line Items]
Proposed settled recoverability cap	7.50%