- 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

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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- Definition

Line Items for Regulatory Matters Pending Rate Cases [Table]

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Percentage of public utility's requested return on equity.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
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Regulatory Matters - Schedule of Pending Rate Cases (Details) - USD ($) $ in Millions	Sep. 01, 2021	Apr. 16, 2021	Mar. 30, 2021
Commonwealth Edison Co [Member] \| Illinois 2021 Electric Distribution Base Rate Case
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)		$ 51
Requested Return on Equity, Percentage		7.36%
Public Utilities, Requested Rate Increase (Decrease), Initial Revenue Requirement, Amount		$ 40
Public Utilities Requested Rate Increase (Decrease), Prior Year Annual Reconciliation		$ 11
Requested Return on Distribution Rate Base, Percentage		5.72%
Basis points for ComEd's Revenue Requirement		580
Commonwealth Edison Co [Member] \| Illinois 2021 Electric Distribution Base Rate Case 2020 Reconciliation
Regulatory Matters Pending Rate Cases [Line Items]
Requested Return on Equity, Percentage		7.29%
Requested Return on Distribution Rate Base, Percentage		5.69%
Basis points for ComEd's Revenue Requirement		580
Commonwealth Edison Co [Member] \| Illinois 2021 Electric Distribution Base Rate Case 2020 Reconciliation \| Performance Metrics Penalty
Regulatory Matters Pending Rate Cases [Line Items]
Basis points for ComEd's Revenue Requirement		7
PECO Energy Co [Member] \| Pennsylvania 2021 Electric Distribution Base Rate Case
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)			$ 246
Requested Return on Equity, Percentage			10.95%
Delmarva Power and Light Company [Member] \| Maryland 2021 Electric Distribution Base Rate Case
Regulatory Matters Pending Rate Cases [Line Items]
Requested Revenue Requirement Increase (Decrease)	$ 29
Requested Return on Equity, Percentage	10.10%