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v3.6.0.2

Leases (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Rentals for capital and operating leases |  |  |
Operating leases | $ 168 | $ 174 | $ 199
FES |  |  |
Rentals for capital and operating leases |  |  |
Operating leases | $ 94 | $ 94 | $ 95

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- Definition Capital leases and operating leases rent expense. + References No definition available. + Details
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Namespace Prefix: | fe_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Definition Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line. + References No definition available. + Details
Name: | us-gaap_LeaseAndRentalExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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- Details
Name: | dei_LegalEntityAxis=fe_FesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |