Number of long term power purchase agreements maintained by parent company with Non utility generation entities.

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- Definition

Number of variable interest contracts.

+ References

No definition available.

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- Definition

Public Utilities, Increase In Plant Ownership Percentage

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No definition available.

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- Definition

Sale Leaseback Transaction, Percentage Of Leasehold Interest Related to Sale Leaseback Arrangement

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No definition available.

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- Definition

Variable interest entities percentage of high voltage transmission line project owned By variable interest entity one in joint venture party one.

+ References

No definition available.

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- Definition

Variable Interest Entities Percentage of high voltage transmission line project owned By variable interest entity one in joint venture party two.

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No definition available.

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- Definition

Variable Interest Entities.

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No definition available.

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- Definition

All amounts that, per contract, are due to the servicer in exchange for servicing the financial asset and would no longer be received by a servicer if the beneficial owners of the serviced assets (or their trustees or agents) were to exercise their actual or potential authority under the contract to shift the servicing to another servicer. Depending on the servicing contract, those fees may include some or all of the difference between the interest rate collected on the asset being serviced and the rate to be paid to the beneficial owners of the asset.

+ References

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-Publisher FASB
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-Subparagraph (c)
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- Definition

Cost of electricity purchased as well as fuel used to generate electricity used in operations and sold during the reporting period.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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-Name Accounting Standards Codification
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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Represents the current and noncurrent portions of a debt security issued by a state, certain agencies or authorities, a local government, or development corporation to finance the construction of air- or water-pollution control facilities or sewage or solid waste disposal facilities pursuant to federal law. The bonds are backed by the credit of the beneficiary of the financing rather than the credit of the issuer.

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Long-Term transition bonds are bonds under the Competition Act in which the proceeds of Transition Bonds are required to be used principally to reduce qualified stranded costs and the related capitalization of the utility. This represents the current and noncurrent portions. The initial maturity is beyond one year or beyond the normal operating cycle, if longer.

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The cash outflow associated with the purchase of noncontrolling interest during the period.

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Variable Interest Entities (Details Textuals)		3 Months Ended		6 Months Ended
Variable Interest Entities (Details Textuals)	Jun. 01, 2017 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) agreement entity	Jun. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Variable Interest Entities (Textuals) [Abstract]
Long-term transition bond		$ 63,000,000		$ 63,000,000		$ 85,000,000
Long-term pollution control bond		395,000,000		395,000,000		406,000,000
Guarantor obligations		420,000,000		$ 420,000,000
Number of contracts that may contain variable interest \| entity				1
Purchased power		$ 735,000,000	$ 889,000,000	$ 1,598,000,000	$ 2,013,000,000
Bruce Mansfield Unit 1
Variable Interest Entities (Textuals) [Abstract]
Percentage of undivided interest of non guarantor subsidiary		93.83%		93.83%
Power Purchase Agreements
Variable Interest Entities (Textuals) [Abstract]
Ownership interest		0.00%		0.00%
Number of long-term power purchase agreements maintained by FirstEnergy with NUG entities \| agreement				12
Phase In Recovery Bonds
Variable Interest Entities (Textuals) [Abstract]
Long-term debt and other long-term obligations		$ 327,000,000		$ 327,000,000		$ 339,000,000
Ohio Funding Companies
Variable Interest Entities (Textuals) [Abstract]
Annual servicing fees				$ 445,000
Other FE subsidiaries
Variable Interest Entities (Textuals) [Abstract]
Ownership interest		0.00%		0.00%
Other FE subsidiaries \| Power Purchase Agreements
Variable Interest Entities (Textuals) [Abstract]
Purchased power		$ 25,000,000	$ 25,000,000	$ 53,000,000	$ 56,000,000
NG \| Beaver Valley Unit 2
Variable Interest Entities (Textuals) [Abstract]
Increase in plant ownership percentage (percent)	2.60%
Amount of irrevocable repurchase right	$ 38,000,000
Path-WV
Variable Interest Entities (Textuals) [Abstract]
Percentage of high-voltage transmission line project owned by subsidiary of FE on the Allegheny Series		100.00%		100.00%
Percentage of high-voltage transmission line project owned by subsidiary of FE on the West Virginia Series		50.00%		50.00%
Global Holding \| Guarantee of senior secured loan facility
Variable Interest Entities (Textuals) [Abstract]
Guarantor obligations		$ 300,000,000		$ 300,000,000
Signal Peak \| Global Holding \| FEV
Variable Interest Entities (Textuals) [Abstract]
Ownership interest		33.33%		33.33%