Basic terms of operating lease.

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- Definition

Leases.

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No definition available.

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- Definition

Operating lease term of Other Subsidiaries .

+ References

No definition available.

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- Definition

Percentage of undivided interest of non guarantor subsidiary.

+ References

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- Definition

Public Utilities, Increase In Plant Ownership Percentage

+ References

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- Definition

Public Utilities, Plant Ownership Percentage

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

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- Definition

Subsidiary one Operating lease term of Subsidiary one.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

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- Definition

The cash outflow associated with the acquisition of or advances to an entity that is related to it but not strictly controlled (for example, an unconsolidated subsidiary, affiliate, and joint venture or equity method investment) or the acquisition of an additional interest in a subsidiary (controlled entity).

+ References

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Leases (Details Textuals) - USD ($) $ in Millions					12 Months Ended
Leases (Details Textuals) - USD ($) $ in Millions	Jun. 01, 2017	Jun. 30, 2016	May 30, 2016	May 23, 2016	Dec. 31, 2007	Dec. 30, 1987	Dec. 31, 2017
Leases (Textuals) [Abstract]
Period of lease terms on the portions sold by OE of its ownership interests in Perry Unit 1 and Beaver Valley Unit 2 in years						29 years
Period of lease terms on the portions sold by CEI and TE of their ownership interests in Beaver Valley Unit 2 and Bruce Mansfield Units						30 years
Bruce Mansfield Unit 1
Leases (Textuals) [Abstract]
Percentage of leasehold interest related to sale leaseback arrangements							93.83%
Percentage leased							93.83%
Perry Power Plant Unit 1
Leases (Textuals) [Abstract]
Percentage of leasehold interest related to sale leaseback arrangements				3.75%
FG
Leases (Textuals) [Abstract]
Percentage of undivided interest of FGCO in Bruce Mansfield Unit 1					93.825%
FG \| Bruce Mansfield Unit 1
Leases (Textuals) [Abstract]
Basic terms of operating lease					33 years
NG \| Beaver Valley Unit 2
Leases (Textuals) [Abstract]
Increase in plant ownership percentage	2.60%
Payments to acquire additional interest in subsidiaries	$ 38
NG \| Perry Power Plant Unit 1
Leases (Textuals) [Abstract]
Payments to acquire interest in subsidiaries				$ 50
Plant ownership percentage		100.00%	100.00%