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, Plant Ownership Percentage

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- Definition

Sale Leaseback Transaction, Percentage Of Undivided Interest Of Non Guarantor Subsidiary

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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.

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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 two.

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No definition available.

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- Definition

Variable Interest Entities.

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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
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 2
-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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
-Subparagraph (SX 210.5-03.2(b))
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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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- 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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- Definition

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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Variable Interest Entities (Details Textuals)			12 Months Ended
Variable Interest Entities (Details Textuals)	Jun. 30, 2016	May 30, 2016	Dec. 31, 2016 USD ($) agreement entity	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Variable Interest Entities (Textuals) [Abstract]
Transition bond outstanding			$ 85,000,000	$ 128,000,000
Environmental control bonds outstanding			$ 406,000,000	429,000,000
Number of contracts that may contain variable interest \| entity			1
Ownership interest (percent)			3.00%
Purchased power			$ 3,813,000,000	4,318,000,000	$ 4,716,000,000
Power Purchase Agreements
Variable Interest Entities (Textuals) [Abstract]
Number of long-term power purchase agreements maintained by FirstEnergy with NUG entities \| agreement			14
Path-WV
Variable Interest Entities (Textuals) [Abstract]
Percentage of high-voltage transmission line project owned by subsidiary of AE on the Allegheny Series			100.00%
Percentage of high-voltage transmission line project owned by subsidiary of AE on the West Virginia Series			50.00%
Other FE subsidiaries
Variable Interest Entities (Textuals) [Abstract]
Ownership interest (percent)			0.00%
Other FE subsidiaries \| Power Purchase Agreements
Variable Interest Entities (Textuals) [Abstract]
Purchased power			$ 108,000,000	116,000,000
Ohio Funding Companies
Variable Interest Entities (Textuals) [Abstract]
Aggregate annual servicing fees receivable for phase-in recovery bonds			$ 445,000
Global Holding \| FEV \| Signal Peak
Variable Interest Entities (Textuals) [Abstract]
Ownership interest (percent)			33.33%
Phase In Recovery Bonds
Variable Interest Entities (Textuals) [Abstract]
Long-term debt and other long-term obligations			$ 339,000,000	$ 362,000,000
Senior Loans \| Senior Secured Term Loan \| Global Holding
Variable Interest Entities (Textuals) [Abstract]
Long-term debt and other long-term obligations			$ 300,000,000
Perry Power Plant Unit 1 \| NG
Variable Interest Entities (Textuals) [Abstract]
Plant ownership percentage	100.00%	100.00%
Bruce Mansfield Unit 1
Variable Interest Entities (Textuals) [Abstract]
Percentage leased			93.83%
Beaver Valley Unit 2
Variable Interest Entities (Textuals) [Abstract]
Percentage leased			2.60%