COMMITMENTS, GUARANTEES AND CONTINGENCIES - Schedule of Guarantor Obligations (Details) $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($)
Guarantor Obligations [Line Items]
Potential additional collateral obligations	$ 359
Percent of face amount of debt	100.00%
Curing period	30 days
Utilities and FET
Guarantor Obligations [Line Items]
Potential additional collateral obligations	$ 101
FE
Guarantor Obligations [Line Items]
Potential additional collateral obligations	258
Upon Further Downgrade
Guarantor Obligations [Line Items]
Potential additional collateral obligations	44
Upon Further Downgrade \| Utilities and FET
Guarantor Obligations [Line Items]
Potential additional collateral obligations	44
Upon Further Downgrade \| FE
Guarantor Obligations [Line Items]
Potential additional collateral obligations	0
Surety Bond
Guarantor Obligations [Line Items]
Potential additional collateral obligations	$ 315
Percent of face amount of debt	60.00%
Capped portion of surety bond obligations	$ 39
Surety Bond \| Utilities and FET
Guarantor Obligations [Line Items]
Potential additional collateral obligations	57
Surety Bond \| FE
Guarantor Obligations [Line Items]
Potential additional collateral obligations	$ 258

Guarantor Obligations, Capped Portion of Surety Bond Obligations

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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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+ References

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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=124440162&loc=d3e12069-110248

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