XML 67 R52.htm IDEA: XBRL DOCUMENT
v3.5.0.2

Fair Value Measurements (Details 4) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2016 | Sep. 30, 2015
Proceeds from the sale of investments in available-for-sale securities, realized gains and losses on those sales, and interest and dividend income |  |  |  |
Sales Proceeds | $ 337 | $ 307 | $ 1,361 | $ 1,126
Realized Gains | 36 | 33 | 131 | 135
Realized Losses | (15) | (32) | (88) | (121)
OTTI | (3) | (46) | (13) | (70)
Interest and Dividend Income | 27 | 25 | 75 | 75
FES |  |  |  |
Proceeds from the sale of investments in available-for-sale securities, realized gains and losses on those sales, and interest and dividend income |  |  |  |
Sales Proceeds | 135 | 127 | 576 | 503
Realized Gains | 23 | 28 | 90 | 98
Realized Losses | (6) | (24) | (49) | (79)
OTTI | (3) | (41) | (12) | (63)
Interest and Dividend Income | $ 16 | $ 14 | $ 42 | $ 43

X
- Definition Investment Income From Trusts + References No definition available. + Details
Name: | fe_InvestmentIncomeFromTrusts
Namespace Prefix: | fe_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesGrossRealizedGainLossAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesGrossRealizedGains
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The total amount of proceeds received for the sale of securities, categorized neither as held-to-maturity nor trading securities, during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesGrossRealizedGainsLossesSaleProceeds
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesGrossRealizedLosses
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of other than temporary impairment losses on investments in debt and equity securities categorized as Available-for-sale which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) on equity securities, credit losses on investments in debt securities, and when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563 + Details
Name: | us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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