Capping Of Gas One Emissions Under Cross State Air Pollution Rule

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Capping Of Gas Two Emissions Under Cross State Air Pollution Rule

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Decommission fund to pay for the costs of decontaminating and decommissioning of facilities through collection of revenues derived from utility assessments and government appropriations. Decommission fund investment for the process whereby a power station, at the end of its economic life, is taken permanently out of service and its site made available for other purposes. In the case of a nuclear station this comprises three different states of clearance. Immediately after the final closure, radioactive material such as nuclear fuel and operational waste is removed and the buildings surrounding the reactor shield are dismantled and finally the reactor itself is dismantled.

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Commitments, Guarantees and Contingencies - Narrative (Details) T in Millions	9 Months Ended
	Sep. 30, 2019 USD ($) phase T	Dec. 31, 2018 USD ($)
Guarantor Obligations [Line Items]
Outstanding guarantees and other assurances aggregated	$ 1,600,000,000
Proposed goal to reduce CO2 pollution (percent)	90.00%
Nuclear plant decommissioning trusts	$ 871,000,000	$ 790,000,000
Clean Water Act
Guarantor Obligations [Line Items]
Waste water discharge permit renewal cycle	5 years
Regulation of Waste Disposal
Guarantor Obligations [Line Items]
Accrual for environmental loss contingencies	$ 119,000,000
Environmental liabilities former gas facilities	$ 83,000,000
National Ambient Air Quality Standards
Guarantor Obligations [Line Items]
Capping of SO2 Emissions Under CSAPR \| T	2.4
Capping of NOx emissions under CSAPR \| T	1.2
National Ambient Air Quality Standards \| CSAPR
Guarantor Obligations [Line Items]
Number of phases under the EPA’s CAIR for reductions of Sulfur Dioxide and Mono-Nitrogen Oxides \| phase	2
Regulated Distribution
Guarantor Obligations [Line Items]
Company posted collateral related to net liability positions	$ 2,000,000
Global Holding \| Senior Secured Term Loan \| Senior Loans \| Signal Peak, Global Rail and Affiliates
Guarantor Obligations [Line Items]
Investment ownership percentage	69.99%
FEV \| Senior Secured Term Loan \| Senior Loans \| Signal Peak \| Global Holding
Guarantor Obligations [Line Items]
Investment ownership percentage	33.33%
WMB Marketing Ventures, LLC \| Senior Secured Term Loan \| Senior Loans \| Signal Peak \| Global Holding
Guarantor Obligations [Line Items]
Investment ownership percentage	33.33%
AE Supply
Guarantor Obligations [Line Items]
Company posted collateral related to net liability positions	$ 0
JCP&L, ME and PN \| Nuclear Plant Matters \| Financial Guarantee
Guarantor Obligations [Line Items]
Nuclear plant decommissioning trusts	900,000,000
FES and FENOC
Guarantor Obligations [Line Items]
Outstanding guarantees and other assurances aggregated	343,000,000
FE
Guarantor Obligations [Line Items]
Outstanding guarantees and other assurances aggregated	1,000,000,000
Other Guarantee
Guarantor Obligations [Line Items]
Outstanding guarantees and other assurances aggregated	145,000,000
Other Guarantees and Assurances
Guarantor Obligations [Line Items]
Outstanding guarantees and other assurances aggregated	301,000,000
Term Loan Facility Due March 2020 \| Line of Credit \| Global Holding
Guarantor Obligations [Line Items]
Face amount of debt	300,000,000
Little Bull Run \| Line of Credit \| Surety Bond (Collateralized Amount)
Guarantor Obligations [Line Items]
Maximum amount borrowed under revolving credit facility	169,000,000
Hatfield Ferry \| Line of Credit \| Surety Bond (Collateralized Amount)
Guarantor Obligations [Line Items]
Maximum amount borrowed under revolving credit facility	$ 31,000,000