Annual Energy Savings, Annual Increase, Percent

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Annual Energy Savings, Cumulative Benchmark, Percent

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Annual Revenue Cap for Rider For Years One Through Three

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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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- Definition

Energy Efficient Portfolio Plan, Term of Plan

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Portfolio Plan, Estimated Cost

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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

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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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- Definition

Regulatory matters.

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Utilities Required To Additionally Reduce Peak Demand

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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					12 Months Ended
Regulatory Matters - Ohio (Details) $ in Millions	Dec. 01, 2017 USD ($)	Oct. 12, 2016 USD ($)	Apr. 15, 2016	Aug. 07, 2013 USD ($) auction	Dec. 31, 2017 USD ($)	Feb. 15, 2018 USD ($)
Regulatory Matters [Line Items]
Proposed reduction in power plants carbon pollution (percent)					90.00%
Ohio
Regulatory Matters [Line Items]
Cumulative benchmark of annual energy savings					22.20%
Energy efficient portfolio plan term			3 years
Portfolio plan estimated cost					$ 268.0
Credit to non-shopping customers				$ 43.4
Ohio \| Year 2017
Regulatory Matters [Line Items]
Annual energy savings yearly increase (percent)					1.00%
Ohio \| Annually Through 2020
Regulatory Matters [Line Items]
Utilities required to additionally reduce peak demand					0.75%
Ohio \| Years 2021 Through 2027
Regulatory Matters [Line Items]
Annual energy savings yearly increase (percent)					2.00%
Ohio \| Distribution Modernization Rider
Regulatory Matters [Line Items]
Rider valuation		$ 558.0
Rider valuation period		8 years
Ohio \| PUCO
Regulatory Matters [Line Items]
Proposed reduction in power plants carbon pollution (percent)		90.00%
Number of renewable energy auctions \| auction				1
Ohio \| PUCO \| Distribution Modernization Rider
Regulatory Matters [Line Items]
Annual revenue cap for rider		$ 132.5
Cost recovery period		3 years
Possible extension period		2 years
Approved annual revenue cap amount for rider		$ 204.0
Excessive earnings test cost recovery exclusion period		3 years
Potential extension period for excessive earnings test cost recovery		2 years
Ohio \| PUCO \| DCR Rider
Regulatory Matters [Line Items]
Increased annual revenue cap for rider		$ 30.0
Revenue cap for Rider for years 3-6		20.0
Revenue cap for Rider for years 6-8		15.0
Ohio \| PUCO \| DPM Plan
Regulatory Matters [Line Items]
Requested rate increase (decrease)	$ 450.0
Ohio \| PUCO \| Energy Conservation, Economic Development and Job Retention
Regulatory Matters [Line Items]
Contribution amount		$ 51.0
Ohio Companies \| Subsequent Event \| Ohio \| PUCO
Regulatory Matters [Line Items]
Impact on base rate due to Tax Act						$ 40.0