Regulatory Matters - Schedule of Completed Rate Cases (Details) - USD ($) $ in Millions																					11 Months Ended	12 Months Ended	48 Months Ended
	Dec. 18, 2023	Dec. 14, 2023	Nov. 30, 2023	Nov. 17, 2023	Aug. 21, 2023	Apr. 21, 2023	Feb. 17, 2023	Jan. 17, 2023	Dec. 14, 2022	Nov. 17, 2022	Oct. 27, 2022	May 19, 2022	Apr. 15, 2022	Mar. 31, 2022	Feb. 23, 2022	Dec. 22, 2021	Jun. 28, 2021	Mar. 31, 2021	Dec. 16, 2020	Sep. 11, 2020	Dec. 17, 2023	Dec. 31, 2023	Dec. 31, 2027	Jun. 30, 2027	Jun. 30, 2023
Commonwealth Edison Co | 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 | 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 | 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 | 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%
Commonwealth Edison Co | Illinois 2023 Electric Distribution Base Rate Case
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount								$ 1,487													$ 1,487
Public Utilities, Approved Rate Increase (Decrease), Amount		$ 501
Public Utilities, Approved Return on Equity, Percentage		8.905%
Commonwealth Edison Co | Illinois 2023 Electric Distribution Base Rate Case | Forecast
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Debt Capital Structure, Percentage																							50.00%
Commonwealth Edison Co | Illinois 2023 Electric Distribution Base Rate Case | 2023 | Forecast
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																							$ 986
Commonwealth Edison Co | Illinois 2023 Electric Distribution Base Rate Case | 2024
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount		$ 451
Commonwealth Edison Co | Illinois 2023 Electric Distribution Base Rate Case | 2025
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount		14
Commonwealth Edison Co | Illinois 2023 Electric Distribution Base Rate Case | 2026
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount		6
Commonwealth Edison Co | Illinois 2023 Electric Distribution Base Rate Case | 2027
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount		30
Commonwealth Edison Co | Illinois 2023 Electric Distribution Reconciliation Rate Case
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount			$ 259
Public Utilities, Approved Return on Equity, Percentage			8.91%
Public Utilities Requested Rate Increase (Decrease), Prior Year Annual Reconciliation						$ 247
Public Utilities, Approved Equity Capital Structure, Percentage			6.48%
Commonwealth Edison Co | Illinois 2023 Electric Distribution Reconciliation Rate Case | 2023
Regulatory Matters Completed Rate Cases [Line Items]
Basis points for ComEd's Revenue Requirement			580
PECO Energy Co | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | Maryland 2020 Gas Distribution Base Rate Case [Member] | 2023
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																			$ 10
Baltimore Gas and Electric Company | Maryland 2023 Electric Distribution Base Rate Case
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount							$ 313
Public Utilities, Approved Rate Increase (Decrease), Amount		$ 179
Public Utilities, Approved Return on Equity, Percentage		9.50%
Baltimore Gas and Electric Company | Maryland 2023 Electric Distribution Base Rate Case | 2024
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount	$ 41
Baltimore Gas and Electric Company | Maryland 2023 Electric Distribution Base Rate Case | 2025
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount	113
Baltimore Gas and Electric Company | Maryland 2023 Electric Distribution Base Rate Case | 2026
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount	25
Baltimore Gas and Electric Company | Maryland 2023 Gas Distribution Base Rate Case
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount							$ 289
Public Utilities, Approved Rate Increase (Decrease), Amount		$ 229
Public Utilities, Approved Return on Equity, Percentage		9.45%
Baltimore Gas and Electric Company | Maryland 2023 Gas Distribution Base Rate Case | 2024
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount	126
Baltimore Gas and Electric Company | Maryland 2023 Gas Distribution Base Rate Case | 2025
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount	62
Baltimore Gas and Electric Company | Maryland 2023 Gas Distribution Base Rate Case | 2026
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount	$ 41
Baltimore Gas and Electric Company | Maryland 2023 Electric Distribution Reconciliation Rate Case [Member] | 2021
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																						$ 13
Baltimore Gas and Electric Company | Maryland 2023 Electric Distribution Reconciliation Rate Case [Member] | 2022
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																						39
Baltimore Gas and Electric Company | Maryland 2023 Gas Distribution Reconciliation Rate Case [Member] | 2021
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																						7
Baltimore Gas and Electric Company | Maryland 2023 Gas Distribution Reconciliation Rate Case [Member] | 2022
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																						$ 15
Potomac Electric Power Company | 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 | 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 | 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 | 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 | Maryland 2020 Electric Distribution Base Rate Case [Member] | 2024
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																	$ 15
Delmarva Power & Light Company | Maryland 2022 Electric Distribution Base Rate Case
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount												$ 38
Public Utilities, Approved Rate Increase (Decrease), Amount									$ 29
Public Utilities, Approved Return on Equity, Percentage									9.60%
Delmarva Power & Light Company | 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 | 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 | Maryland 2022 Electric Distribution Base Rate Case | 2025
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount									$ 6
Atlantic City Electric Company
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																									$ 96
Atlantic City Electric Company | Forecast
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount																								$ 93
Atlantic City Electric Company | New Jersey 2023 Electric Distribution Base Rate Case
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount					$ 92
Public Utilities, Approved Rate Increase (Decrease), Amount				$ 45
Public Utilities, Approved Return on Equity, Percentage				9.60%
Atlantic City Electric Company | New Jersey 2023 Electric Distribution Base Rate Case | 2023
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount				$ 36
Atlantic City Electric Company | New Jersey 2023 Electric Distribution Base Rate Case | 2024
Regulatory Matters Completed Rate Cases [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount				$ 9