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Commitments, Guarantees and Contingencies (Details) $ in Millions | Dec. 31, 2017 USD ($)
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Guarantor Obligations [Line Items] |
Potential additional collateral obligations | $ 407
Regulated Distribution |
Guarantor Obligations [Line Items] |
Potential additional collateral obligations | 148
FE |
Guarantor Obligations [Line Items] |
Potential additional collateral obligations | 237
FES |
Guarantor Obligations [Line Items] |
Potential additional collateral obligations | 20
AE Supply |
Guarantor Obligations [Line Items] |
Potential additional collateral obligations | 2
At Current Credit Rating |
Guarantor Obligations [Line Items] |
Potential additional collateral obligations | 5
At Current Credit Rating | Regulated Distribution |
Guarantor Obligations [Line Items] |
Potential additional collateral obligations | 0
At Current Credit Rating | FE |
Guarantor Obligations [Line Items] |
Potential additional collateral obligations | 0
At Current Credit Rating | FES |
Guarantor Obligations [Line Items] |
Potential additional collateral obligations | 4
At Current Credit Rating | AE Supply |
Guarantor Obligations [Line Items] |
Potential additional collateral obligations | 1
Upon Further Downgrade |
Guarantor Obligations [Line Items] |
Potential additional collateral obligations | 41
Upon Further Downgrade | Regulated Distribution |
Guarantor Obligations [Line Items] |
Potential additional collateral obligations | 41
Upon Further Downgrade | FE |
Guarantor Obligations [Line Items] |
Potential additional collateral obligations | 0
Upon Further Downgrade | FES |
Guarantor Obligations [Line Items] |
Potential additional collateral obligations | 0
Upon Further Downgrade | AE Supply |
Guarantor Obligations [Line Items] |
Potential additional collateral obligations | 0
Surety Bond |
Guarantor Obligations [Line Items] |
Potential additional collateral obligations | 361
Surety Bond | Regulated Distribution |
Guarantor Obligations [Line Items] |
Potential additional collateral obligations | 107
Surety Bond | FE |
Guarantor Obligations [Line Items] |
Potential additional collateral obligations | 237
Surety Bond | FES |
Guarantor Obligations [Line Items] |
Potential additional collateral obligations | 16
Surety Bond | AE Supply |
Guarantor Obligations [Line Items] |
Potential additional collateral obligations | $ 1

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- Definition Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=82913245&loc=d3e12069-110248 + Details
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