Regulatory Matters - Schedule of Completed Rate Cases (Details) - USD ($) $ in Millions	Dec. 14, 2022	Nov. 17, 2022	Oct. 27, 2022	Oct. 12, 2022	Aug. 15, 2022	May 19, 2022	Apr. 15, 2022	Mar. 31, 2022	Mar. 02, 2022	Feb. 23, 2022	Dec. 23, 2021	Dec. 22, 2021	Dec. 01, 2021	Nov. 18, 2021	Jul. 14, 2021	Jun. 28, 2021	Jun. 08, 2021	Apr. 16, 2021	Mar. 31, 2021	Mar. 30, 2021	Feb. 26, 2021	Dec. 16, 2020	Sep. 11, 2020	Jun. 01, 2020
Commonwealth Edison Co [Member] | Illinois 2021 Electric Distribution Base Rate Case
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount																		$ 51
Public Utilities, Approved Rate Increase (Decrease), Amount													$ 46
Public Utilities, Approved Return on Equity, Percentage													7.36%
Commonwealth Edison Co [Member] | Illinois 2021 Electric Distribution Base Rate Case | 2020
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount													$ 9
Public Utilities, Approved Return on Equity, Percentage													7.29%
Basis points for ComEd's Revenue Requirement													580
Public Utilities, Approved Equity Capital Structure, Percentage													5.69%
Commonwealth Edison Co [Member] | Illinois 2021 Electric Distribution Base Rate Case | 2020 | Performance Metrics Penalty
Regulatory Matters Completed Rate Cases [Line Items]
Basis points for ComEd's Revenue Requirement													7
Commonwealth Edison Co [Member] | Illinois 2021 Electric Distribution Base Rate Case | 2022
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount													$ 37
Public Utilities, Approved Return on Equity, Percentage													7.36%
Basis points for ComEd's Revenue Requirement													580
Public Utilities, Approved Equity Capital Structure, Percentage													5.72%
Commonwealth Edison Co [Member] | Illinois 2022 Electric Distribution Base Rate Case
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount							$ 199
Public Utilities, Approved Rate Increase (Decrease), Amount		$ 199
Public Utilities, Approved Return on Equity, Percentage		7.85%
Commonwealth Edison Co [Member] | Illinois 2022 Electric Distribution Base Rate Case | 2021
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Return on Equity, Percentage		7.78%
Basis points for ComEd's Revenue Requirement		580
Public Utilities Approved Rate Increase (Decrease), Prior Year Annual Reconciliation		$ 55
Public Utilities, Approved Equity Capital Structure, Percentage		5.91%
Commonwealth Edison Co [Member] | Illinois 2022 Electric Distribution Base Rate Case | 2021 | Performance Metrics Penalty
Regulatory Matters Completed Rate Cases [Line Items]
Basis points for ComEd's Revenue Requirement		7
Commonwealth Edison Co [Member] | Illinois 2022 Electric Distribution Base Rate Case | 2023
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount		$ 144
Public Utilities, Approved Return on Equity, Percentage		7.85%
Basis points for ComEd's Revenue Requirement		580
Public Utilities, Approved Equity Capital Structure, Percentage		5.94%
PECO Energy Co [Member] | Pennsylvania 2021 Electric Distribution Base Rate Case [Member]
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount																				$ 246
Public Utilities, Approved Rate Increase (Decrease), Amount														$ 132
PECO Energy Co [Member] | Pennsylvania 2022 Natural Gas Distribution Base Rate Case
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount								$ 82
Public Utilities, Approved Rate Increase (Decrease), Amount			$ 55
Baltimore Gas and Electric Company [Member] | Maryland 2020 Electric Distribution Base Rate Case [Member]
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount																							$ 203
Public Utilities, Approved Rate Increase (Decrease), Amount																						$ 140
Public Utilities, Approved Return on Equity, Percentage																						9.50%
Baltimore Gas and Electric Company [Member] | Maryland 2020 Electric Distribution Base Rate Case [Member] | 2021
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																						$ 59
Baltimore Gas and Electric Company [Member] | Maryland 2020 Electric Distribution Base Rate Case [Member] | 2022
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																						39
Baltimore Gas and Electric Company [Member] | Maryland 2020 Electric Distribution Base Rate Case [Member] | 2022 | Offsets
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Percentage												25.00%
Baltimore Gas and Electric Company [Member] | Maryland 2020 Electric Distribution Base Rate Case [Member] | 2023
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																						42
Baltimore Gas and Electric Company [Member] | Maryland 2020 Gas Distribution Base Rate Case [Member]
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount																							$ 108
Public Utilities, Approved Rate Increase (Decrease), Amount																						$ 74
Public Utilities, Approved Return on Equity, Percentage																						9.65%
Baltimore Gas and Electric Company [Member] | Maryland 2020 Gas Distribution Base Rate Case [Member] | 2021
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																						$ 53
Baltimore Gas and Electric Company [Member] | Maryland 2020 Gas Distribution Base Rate Case [Member] | 2022
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																						11
Baltimore Gas and Electric Company [Member] | Maryland 2020 Gas Distribution Base Rate Case [Member] | 2022 | Offsets
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Percentage												50.00%
Baltimore Gas and Electric Company [Member] | Maryland 2020 Gas Distribution Base Rate Case [Member] | 2023
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																						$ 10
Potomac Electric Power Company [Member] | Maryland 2020 Electric Distribution Base Rate Case [Member]
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount																			$ 104
Public Utilities, Approved Rate Increase (Decrease), Amount																$ 52
Public Utilities, Approved Return on Equity, Percentage																9.55%
Potomac Electric Power Company [Member] | Maryland 2020 Electric Distribution Base Rate Case [Member] | 2022
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																$ 21
Potomac Electric Power Company [Member] | Maryland 2020 Electric Distribution Base Rate Case [Member] | 2023
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																16
Potomac Electric Power Company [Member] | Maryland 2020 Electric Distribution Base Rate Case [Member] | 2023 | Offsets
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Percentage										25.00%
Potomac Electric Power Company [Member] | Maryland 2020 Electric Distribution Base Rate Case [Member] | 2024
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																$ 15
Potomac Electric Power Company [Member] | District of Columbia 2019 Electric Distribution Base Rate Case
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount																								$ 136
Public Utilities, Approved Rate Increase (Decrease), Amount																	$ 109
Public Utilities, Approved Return on Equity, Percentage																	9.275%
Potomac Electric Power Company [Member] | District of Columbia 2019 Electric Distribution Base Rate Case | 2021
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																	$ 42
Potomac Electric Power Company [Member] | District of Columbia 2019 Electric Distribution Base Rate Case | 2021 | Offsets
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																	(22)
Potomac Electric Power Company [Member] | District of Columbia 2019 Electric Distribution Base Rate Case | 2022
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																	67
Potomac Electric Power Company [Member] | District of Columbia 2019 Electric Distribution Base Rate Case | 2022 | Offsets
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																	$ (40)
Delmarva Power & Light Company [Member] | Maryland 2021 Electric Distribution Base Rate Case
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount											$ 27
Public Utilities, Approved Rate Increase (Decrease), Amount									$ 13
Public Utilities, Approved Return on Equity, Percentage									9.60%
Delmarva Power & Light Company [Member] | Maryland 2022 Electric Distribution Base Rate Case
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount						$ 38
Public Utilities, Approved Rate Increase (Decrease), Amount	$ 29
Public Utilities, Approved Return on Equity, Percentage	9.60%
Delmarva Power & Light Company [Member] | Maryland 2022 Electric Distribution Base Rate Case | 2023
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount	$ 17
Delmarva Power & Light Company [Member] | Maryland 2022 Electric Distribution Base Rate Case | 2024
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount	6
Delmarva Power & Light Company [Member] | Maryland 2022 Electric Distribution Base Rate Case | 2025
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount	$ 6
Delmarva Power & Light Company [Member] | Delaware 2022 Natural Gas Distribution Base Rate Case
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount					$ 13
Public Utilities, Approved Rate Increase (Decrease), Amount				$ 8
Public Utilities, Approved Return on Equity, Percentage				9.60%
Atlantic City Electric Company [Member] | New Jersey 2020 Electric Distribution Base Rate Case
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount																					$ 67
Public Utilities, Approved Rate Increase (Decrease), Amount															$ 41
Public Utilities, Approved Return on Equity, Percentage															9.60%
Atlantic City Electric Company [Member] | New Jersey 2020 Electric Distribution Base Rate Case | Tax Benefits
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount															$ 11