- Definition

Maximum basis points that can be added to the average rate on 30-year treasury notes, to determine the allowed ROE for ComEd's revenue requirement.

+ References

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- Definition

Amount of public utility's requested rate increase (decrease) with regulatory agency, initial revenue requirement.

+ References

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- Definition

Amount of public utility's requested rate increase (decrease) with regulatory agency, prior year annual reconciliation.

+ References

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- Definition

Public Utilities, Requested Rate Increase (Decrease), Proposed Revenue Requirement Phase-In

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- Definition

Line Items for Regulatory Matters Pending Rate Cases [Table]

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- Definition

Percentage of public utility's approved return on equity.

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- Definition

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

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- Definition

Amount of public utility's amended requested rate increase (decrease) with regulatory agency.

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- Definition

Amount of public utility's requested rate increase (decrease) with regulatory agency.

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- Definition

Percentage of public utility's requested return on equity.

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Regulatory Matters - Schedule of Pending Rate Cases (Details) $ in Millions								3 Months Ended
	Apr. 21, 2023 USD ($)	Apr. 13, 2023 USD ($)	Feb. 28, 2023 USD ($)	Feb. 17, 2023 USD ($)	Feb. 15, 2023 USD ($)	Jan. 17, 2023 USD ($)	Feb. 03, 2022	Mar. 31, 2023 USD ($)	Mar. 31, 2022 USD ($)
Regulatory Matters Pending Rate Cases [Line Items]
Basis points for ComEd's Revenue Requirement							580
Commonwealth Edison Co [Member] \| Illinois 2023 Electric Distribution Base Rate Case
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)						$ 1,472
Commonwealth Edison Co [Member] \| Illinois 2023 Electric Distribution Base Rate Case \| Minimum [Member]
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Equity Capital Structure, Percentage						50.58%
Commonwealth Edison Co [Member] \| Illinois 2023 Electric Distribution Base Rate Case \| Maximum [Member]
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Equity Capital Structure, Percentage						51.19%
Commonwealth Edison Co [Member] \| Illinois 2023 Electric Distribution Base Rate Case \| 2023
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Equity Capital Structure, Percentage						7.43%
Commonwealth Edison Co [Member] \| Illinois 2023 Electric Distribution Base Rate Case \| 2024
Regulatory Matters Pending Rate Cases [Line Items]
Requested Return on Equity, Percentage						10.50%
Public Utilities, Requested Rate Increase (Decrease), Initial Revenue Requirement, Amount						$ 877
Commonwealth Edison Co [Member] \| Illinois 2023 Electric Distribution Base Rate Case \| 2025
Regulatory Matters Pending Rate Cases [Line Items]
Requested Return on Equity, Percentage						10.55%
Public Utilities Requested Rate Increase (Decrease), Prior Year Annual Reconciliation						$ 175
Public Utilities, Requested Equity Capital Structure, Percentage						7.50%
Commonwealth Edison Co [Member] \| Illinois 2023 Electric Distribution Base Rate Case \| 2026
Regulatory Matters Pending Rate Cases [Line Items]
Requested Return on Equity, Percentage						10.60%
Public Utilities, Requested Rate Increase (Decrease), Initial Revenue Requirement, Amount						$ 217
Public Utilities, Requested Equity Capital Structure, Percentage						7.62%
Public Utilities, Requested Rate Increase (Decrease), Proposed Revenue Requirement Phase-In						$ 307
Commonwealth Edison Co [Member] \| Illinois 2023 Electric Distribution Base Rate Case \| 2027
Regulatory Matters Pending Rate Cases [Line Items]
Requested Return on Equity, Percentage						10.65%
Public Utilities, Requested Rate Increase (Decrease), Initial Revenue Requirement, Amount						$ 203
Public Utilities, Requested Equity Capital Structure, Percentage						7.70%
Commonwealth Edison Co [Member] \| Illinois 2023 Electric Distribution Reconciliation Rate Case \| Subsequent Event [Member] \| 2022
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities Requested Rate Increase (Decrease), Prior Year Annual Reconciliation	$ 247
Public Utilities, Approved Return on Equity, Percentage	8.91%
Baltimore Gas and Electric Company [Member] \| Maryland 2023 Electric Distribution Base Rate Case
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)				$ 313
Requested Return on Equity, Percentage				10.40%
Baltimore Gas and Electric Company [Member] \| Maryland 2023 Electric Distribution Base Rate Case \| 2024
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)				$ 85
Baltimore Gas and Electric Company [Member] \| Maryland 2023 Electric Distribution Base Rate Case \| 2025
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)				103
Baltimore Gas and Electric Company [Member] \| Maryland 2023 Electric Distribution Base Rate Case \| 2026
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)				125
Baltimore Gas and Electric Company [Member] \| Maryland 2023 Gas Distribution Base Rate Case
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)				$ 289
Requested Return on Equity, Percentage				10.40%
Baltimore Gas and Electric Company [Member] \| Maryland 2023 Gas Distribution Base Rate Case \| 2024
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)				$ 158
Baltimore Gas and Electric Company [Member] \| Maryland 2023 Gas Distribution Base Rate Case \| 2025
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)				77
Baltimore Gas and Electric Company [Member] \| Maryland 2023 Gas Distribution Base Rate Case \| 2026
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)				$ 54
Baltimore Gas and Electric Company [Member] \| Maryland 2023 Electric Distribution Reconciliation Rate Case \| 2022
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)								$ 44
Baltimore Gas and Electric Company [Member] \| Maryland 2023 Electric Distribution Reconciliation Rate Case \| 2021
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)									$ 11
Baltimore Gas and Electric Company [Member] \| Maryland 2023 Gas Distribution Reconciliation Rate Case \| 2022
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)								$ 15
Baltimore Gas and Electric Company [Member] \| Maryland 2023 Gas Distribution Reconciliation Rate Case \| 2021
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)									$ 7
Potomac Electric Power Company [Member] \| District of Columbia 2023 Electric Distribution Base Rate Case
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease), Amended		$ 191
Requested Return on Equity, Percentage		10.50%
Potomac Electric Power Company [Member] \| District of Columbia 2023 Electric Distribution Base Rate Case \| 2024
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)		$ 117
Potomac Electric Power Company [Member] \| District of Columbia 2023 Electric Distribution Base Rate Case \| 2025
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)		37
Potomac Electric Power Company [Member] \| District of Columbia 2023 Electric Distribution Base Rate Case \| 2026
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)		$ 37
Delmarva Power and Light Company [Member] \| Delaware DE 2022 Electric Distribution Base Rate Case
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease), Amended			$ 48
Requested Return on Equity, Percentage			10.50%
Atlantic City Electric Company [Member] \| New Jersey 2023 Electric Distribution Base Rate Case
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease), Amended					$ 105
Requested Return on Equity, Percentage					10.50%