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Annual Revenue Cap for Rider For Years Six Through Eight

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Annual Revenue Cap for Rider For Years Three Through Six

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Credit to Non-Shopping Customers

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Energy Efficient Portfolio Plan, Term of Plan

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Proposed Action, Reduction in Power Plants Carbon Pollution, Percentage

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Public Utilities, Annual Revenue Cap for Rider

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Public Utilities, Annual Revenue Cap for Rider, Approved Amount

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Public Utilities, Contribution Amount

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Public Utilities, Cost Recovery Period

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Public Utilities, Cost Recovery Period, Possible Extension Period

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Public Utilities, Excessive Earnings Test Cost Recovery, Exclusion Period, Renewal Period

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Public Utilities, Renewable Energy Auctions

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Public Utilities, Rider Valuation, Amount

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Public Utilities, Rider Valuation, Period

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Public Utilities, Tax Cuts and Jobs Act of 2017, Impact on Base Rate

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Regulatory matters.

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

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Regulatory Matters - Ohio (Details) $ in Millions						3 Months Ended
Regulatory Matters - Ohio (Details) $ in Millions	Mar. 12, 2018	Dec. 01, 2017 USD ($)	Oct. 12, 2016 USD ($)	Apr. 15, 2016	Aug. 07, 2013 USD ($) auction	Mar. 31, 2018 USD ($)	Feb. 15, 2018 USD ($)
Regulatory Matters [Line Items]
Proposed goal to reduce CO2 pollution (percent)						90.00%
Ohio
Regulatory Matters [Line Items]
Energy efficient portfolio plan term				3 years
Estimated cost of plans						$ 268.0
Credit to non-shopping customers					$ 43.4
Ohio \| PUCO
Regulatory Matters [Line Items]
Proposed goal to reduce CO2 pollution (percent)			90.00%
Requested removal of cost cap	4.00%
Number of renewable energy auctions \| auction					1
Ohio \| Distribution Modernization Rider
Regulatory Matters [Line Items]
Amount of rider valuation			$ 558.0
Period of rider valuation			8 years
Ohio \| Distribution Modernization Rider \| PUCO
Regulatory Matters [Line Items]
Annual revenue cap for rider			$ 132.5
Recovery period			3 years
Possible extension period			2 years
Approved amount for rider			$ 168.0
Excessive earnings test exclusion period			3 years
Renewal period for excessive earnings test exclusion period			2 years
Ohio \| Delivery Capital Recovery Rider \| PUCO
Regulatory Matters [Line Items]
Annual revenue cap for rider			$ 30.0
Annual revenue cap for rider for years three through six			20.0
Annual revenue cap for rider for years six through eight			15.0
Ohio \| Distribution Platform Modernization Plan \| PUCO
Regulatory Matters [Line Items]
Amount of requested rate increase (decrease)		$ 450.0
Ohio \| Energy Conservation, Economic Development and Job Retention \| PUCO
Regulatory Matters [Line Items]
Contribution amount			$ 51.0
The Ohio Companies \| Ohio \| PUCO
Regulatory Matters [Line Items]
Impact on base rate							$ 40.0