Leases (Details Textuals) (USD $) In Millions, unless otherwise specified	12 Months Ended		0 Months Ended	1 Months Ended
	Dec. 30, 1987	Dec. 31, 2007	Feb. 12, 2014 MW	Nov. 30, 2014 MW	Dec. 31, 2014
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
Beaver Valley Unit 2
Leases (Textuals) [Abstract]
Percentage leased					2.60%
Bruce Mansfield Unit 1
Leases (Textuals) [Abstract]
Percentage leased					93.83%
Perry Power Plant Unit 1
Leases (Textuals) [Abstract]
Percentage leased					3.75%
FGCO
Leases (Textuals) [Abstract]
Percentage of undivided interest of FGCO in Bruce Mansfield Unit 1		93.825%
FGCO | Bruce Mansfield Unit 1
Leases (Textuals) [Abstract]
Basic terms of operating lease		33 years
Nuclear Generation Corp | Beaver Valley Unit 2
Leases (Textuals) [Abstract]
Purchase of lessor equity interests in sale and leaseback (in MW)			47.7	55.3
Purchase of lessor equity interests in sale and leaseback, value			$ 94
Nuclear Generation Corp | Perry Power Plant Unit 1
Leases (Textuals) [Abstract]
Purchase of lessor equity interests in sale and leaseback, value				87