Income Taxes	9 Months Ended
Sep. 30, 2016
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES FirstEnergy’s and FES’ interim effective tax rates reflect the estimated annual effective tax rates for 2016 and 2015. These tax rates are affected by estimated annual permanent items, such as AFUDC equity and other flow-through items, as well as discrete items that may occur in any given period, but are not consistent from period to period. FirstEnergy’s effective tax rate for the three months ended September 30, 2016 and 2015 was 39.8% and 36.4%, respectively. Changes in FirstEnergy’s effective tax rate for the nine months ended September 30, 2016 as compared to the same period of 2015, resulted from the second quarter of 2016 impairment of $800 million of goodwill (as described in Note 2), of which $433 million is non-deductible for tax purposes. Additionally, $159 million of valuation allowances were recorded in the second quarter of 2016 against state and local NOL carryforwards that management believes, more likely than not, will not be realized based primarily on projected taxable income reflecting updates to FirstEnergy's annual long-term fundamental pricing model for energy and capacity, as well as certain statutory limitations on the utilization of state and local NOL carryforwards. FES’ effective tax rate for the three months ended September 30, 2016 and 2015 was 58.3% and 36.8%, respectively. The increase in the effective tax rate is primarily due to the impact of estimated annual permanent items on forecasted lower pre-tax income for the period. FES’ effective tax rate for the nine months ended September 30, 2016 and 2015 was 1.8% and 40.0%, respectively. The change in the effective tax rate primarily resulted from $65 million of valuation allowances recorded against state and local NOL carryforwards that management believes, more likely than not, will not be realized as described above. Additionally, FES recorded an impairment of goodwill (as described in Note 2) in the second quarter of 2016, of which $23 million is non-deductible for tax purposes. In March 2016, FirstEnergy recorded unrecognized tax benefits of $69 million primarily related to protective refund claims filed with the Commonwealth of Pennsylvania as a result of a recent ruling by the Commonwealth Court finding that the state’s NOL carryover limitation violated the uniformity clause and was unconstitutional. The Commonwealth of Pennsylvania has appealed this ruling to the Pennsylvania Supreme Court. As of September 30, 2016, it is reasonably possible that approximately $54 million of unrecognized tax benefits may be resolved within the next twelve months as a result of the statute of limitations expiring and expected resolution with respect to certain claims, of which approximately $15 million would affect FirstEnergy's effective tax rate. In February 2016, the IRS completed its examination of FirstEnergy’s 2014 federal income tax return and issued a full acceptance letter with no adjustments.

INCOME TAXES

FirstEnergy’s and FES’ interim effective tax rates reflect the estimated annual effective tax rates for 2016 and 2015. These tax rates are affected by estimated annual permanent items, such as AFUDC equity and other flow-through items, as well as discrete items that may occur in any given period, but are not consistent from period to period.

FirstEnergy’s effective tax rate for the three months ended September 30, 2016 and 2015 was 39.8% and 36.4%, respectively.

Changes in FirstEnergy’s effective tax rate for the nine months ended September 30, 2016 as compared to the same period of 2015, resulted from the second quarter of 2016 impairment of $800 million of goodwill (as described in Note 2), of which $433 million is non-deductible for tax purposes. Additionally, $159 million of valuation allowances were recorded in the second quarter of 2016 against state and local NOL carryforwards that management believes, more likely than not, will not be realized based primarily on projected taxable income reflecting updates to FirstEnergy's annual long-term fundamental pricing model for energy and capacity, as well as certain statutory limitations on the utilization of state and local NOL carryforwards.

FES’ effective tax rate for the three months ended September 30, 2016 and 2015 was 58.3% and 36.8%, respectively. The increase in the effective tax rate is primarily due to the impact of estimated annual permanent items on forecasted lower pre-tax income for the period.

FES’ effective tax rate for the nine months ended September 30, 2016 and 2015 was 1.8% and 40.0%, respectively. The change in the effective tax rate primarily resulted from $65 million of valuation allowances recorded against state and local NOL carryforwards that management believes, more likely than not, will not be realized as described above. Additionally, FES recorded an impairment of goodwill (as described in Note 2) in the second quarter of 2016, of which $23 million is non-deductible for tax purposes.

In March 2016, FirstEnergy recorded unrecognized tax benefits of $69 million primarily related to protective refund claims filed with the Commonwealth of Pennsylvania as a result of a recent ruling by the Commonwealth Court finding that the state’s NOL carryover limitation violated the uniformity clause and was unconstitutional. The Commonwealth of Pennsylvania has appealed this ruling to the Pennsylvania Supreme Court.

As of September 30, 2016, it is reasonably possible that approximately $54 million of unrecognized tax benefits may be resolved within the next twelve months as a result of the statute of limitations expiring and expected resolution with respect to certain claims, of which approximately $15 million would affect FirstEnergy's effective tax rate.

In February 2016, the IRS completed its examination of FirstEnergy’s 2014 federal income tax return and issued a full acceptance letter with no adjustments.