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Commitments, Guarantees and Contingencies (Details) $ in Millions | 9 Months Ended
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Sep. 30, 2018 USD ($)
Guarantor Obligations [Line Items] |
Guarantor obligations | $ 362
Curing period | 30 days
At Current Credit Rating |
Guarantor Obligations [Line Items] |
Guarantor obligations | $ 1
Upon Further Downgrade |
Guarantor Obligations [Line Items] |
Guarantor obligations | 54
Surety Bond (Collateralized Amount) |
Guarantor Obligations [Line Items] |
Guarantor obligations | 307
Utilities and FET |
Guarantor Obligations [Line Items] |
Guarantor obligations | 114
Utilities and FET | At Current Credit Rating |
Guarantor Obligations [Line Items] |
Guarantor obligations | 0
Utilities and FET | Upon Further Downgrade |
Guarantor Obligations [Line Items] |
Guarantor obligations | 54
Utilities and FET | Surety Bond (Collateralized Amount) |
Guarantor Obligations [Line Items] |
Guarantor obligations | 60
FirstEnergy |
Guarantor Obligations [Line Items] |
Guarantor obligations | 246
FirstEnergy | At Current Credit Rating |
Guarantor Obligations [Line Items] |
Guarantor obligations | 0
FirstEnergy | Upon Further Downgrade |
Guarantor Obligations [Line Items] |
Guarantor obligations | 0
FirstEnergy | Surety Bond (Collateralized Amount) |
Guarantor Obligations [Line Items] |
Guarantor obligations | 246
AE Supply |
Guarantor Obligations [Line Items] |
Guarantor obligations | 2
AE Supply | At Current Credit Rating |
Guarantor Obligations [Line Items] |
Guarantor obligations | 1
AE Supply | Upon Further Downgrade |
Guarantor Obligations [Line Items] |
Guarantor obligations | 0
AE Supply | Surety Bond (Collateralized Amount) |
Guarantor Obligations [Line Items] |
Guarantor 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=115931803&loc=d3e12069-110248 + Details
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