XML 114 R103.htm IDEA: XBRL DOCUMENT
v3.20.2

Regulatory Matters - Reliability and FERC Matters (Details) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 USD ($)
FERC |
Regulatory Matters [Line Items] |
Denied recovery charges of exit fees | $ 78.8
JCP&L |
Regulatory Matters [Line Items] |
Approved ROE | 9.60%
Approved capital structure | 45.00%

X
- Definition Denied Recovery Charges of Exit Fees + References No definition available. + Details
Name: | fe_DeniedRecoveryChargesOfExitFees
Namespace Prefix: | fe_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Regulatory matters. + References No definition available. + Details
Name: | fe_RegulatoryMattersLineItems
Namespace Prefix: | fe_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of public utility's approved equity to capital, including debt and equity. + References No definition available. + Details
Name: | us-gaap_PublicUtilitiesApprovedEquityCapitalStructurePercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of public utility's approved return on equity. + References No definition available. + Details
Name: | us-gaap_PublicUtilitiesApprovedReturnOnEquityPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_RegulatoryAgencyAxis=fe_FercMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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