Regulatory Matters - Schedule of Pending Rate Cases (Details) - USD ($) $ in Millions	Jan. 17, 2023	Dec. 15, 2022
Commonwealth Edison Co [Member] \| Illinois 2023 Electric Distribution Base Rate Case
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount	$ 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 Return on Equity, Percentage	10.50%
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 Return on Equity, Percentage	10.65%
Public Utilities, Requested Equity Capital Structure, Percentage	51.19%
Commonwealth Edison Co [Member] \| Illinois 2023 Electric Distribution Base Rate Case \| 2024
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Return on Equity, Percentage	10.50%
Public Utilities, Requested Rate Increase (Decrease), Initial Revenue Requirement, Amount	$ 877
Public Utilities, Requested Equity Capital Structure, Percentage	7.43%
Commonwealth Edison Co [Member] \| Illinois 2023 Electric Distribution Base Rate Case \| 2025
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Return on Equity, Percentage	10.55%
Public Utilities, Requested Rate Increase (Decrease), Initial Revenue Requirement, Amount	$ 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]
Public Utilities, 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]
Public Utilities, 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%
Delmarva Power & Light Company [Member] \| Delaware 2022 Electric Distribution Base Rate Case
Regulatory Matters Pending Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount		$ 60
Public Utilities, Requested Return on Equity, Percentage		10.50%

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

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Line Items for Regulatory Matters Pending Rate Cases [Table]

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

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Percentage of public utility's requested return on equity.

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