REGULATORY MATTERS - Distribution Rate Orders (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Jan. 01, 2021
CEI
Public Utilities, General Disclosures [Line Items]
Allowed Debt	51.00%
Allowed Equity	49.00%
Approved ROE	10.50%
ME
Public Utilities, General Disclosures [Line Items]
Allowed Debt	48.80%
Allowed Equity	51.20%
MP
Public Utilities, General Disclosures [Line Items]
Allowed Debt	54.00%
Allowed Equity	46.00%
JCP&L
Public Utilities, General Disclosures [Line Items]
Allowed Debt	48.60%
Allowed Equity	51.40%
Approved ROE	9.60%
Regulatory liabilities		$ 86
OE
Public Utilities, General Disclosures [Line Items]
Allowed Debt	51.00%
Allowed Equity	49.00%
Approved ROE	10.50%
PE \| West Virginia
Public Utilities, General Disclosures [Line Items]
Allowed Debt	54.00%
Allowed Equity	46.00%
PE \| Maryland
Public Utilities, General Disclosures [Line Items]
Allowed Debt	47.00%
Allowed Equity	53.00%
Approved ROE	9.65%
PN
Public Utilities, General Disclosures [Line Items]
Allowed Debt	47.40%
Allowed Equity	52.60%
Penn
Public Utilities, General Disclosures [Line Items]
Allowed Debt	49.90%
Allowed Equity	50.10%
TE
Public Utilities, General Disclosures [Line Items]
Allowed Debt	51.00%
Allowed Equity	49.00%
Approved ROE	10.50%
WP
Public Utilities, General Disclosures [Line Items]
Allowed Debt	49.70%
Allowed Equity	50.30%

Percentage of public utility's approved debt to capital, including debt and equity.

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- Definition

Percentage of public utility's approved equity to capital, including debt and equity.

+ References

No definition available.

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- Definition

Percentage of public utility's approved return on equity.

+ References

No definition available.

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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

The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 405
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6500807&loc=d3e48068-110394

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