COMMITMENTS, GUARANTEES AND CONTINGENCIES - Potential Collateral Obligations (Details) $ in Millions	3 Months Ended
Mar. 31, 2023 USD ($)
Guarantor Obligations [Line Items]
Guarantor obligations	$ 373
Percent of face amount of debt	100.00%
Curing period	30 days
Upon Further Downgrade
Guarantor Obligations [Line Items]
Guarantor obligations	$ 62
Surety Bond (Collateralized Amount)
Guarantor Obligations [Line Items]
Guarantor obligations	$ 311
Percent of face amount of debt	60.00%
Capped portion of surety bond obligations	$ 39
Utilities and Transmission Companies
Guarantor Obligations [Line Items]
Guarantor obligations	124
Utilities and Transmission Companies \| Upon Further Downgrade
Guarantor Obligations [Line Items]
Guarantor obligations	62
Utilities and Transmission Companies \| Surety Bond (Collateralized Amount)
Guarantor Obligations [Line Items]
Guarantor obligations	62
FirstEnergy
Guarantor Obligations [Line Items]
Guarantor obligations	249
FirstEnergy \| Upon Further Downgrade
Guarantor Obligations [Line Items]
Guarantor obligations	0
FirstEnergy \| Surety Bond (Collateralized Amount)
Guarantor Obligations [Line Items]
Guarantor obligations	$ 249

Guarantor Obligations, Capped Portion of Surety Bond Obligations

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- Definition

Guarantor Obligations, Curing Period

+ References

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- Definition

Guarantor Obligations, Maximum Contractual Obligations, Percent of Face Amount of Debt

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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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 https://asc.fasb.org/extlink&oid=124440162&loc=d3e12069-110248

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