Debt and Credit Agreements - Schedule of Long-term Debt Maturities (Details) $ in Millions	Dec. 31, 2023 USD ($)
Debt Instrument [Line Items]
2024	$ 1,403
2025	1,327
2026	1,615
2027	1,023
2028	1,990
Thereafter	33,921
Total	41,279
Related Party \| Long-term debt to financing trusts
Debt Instrument [Line Items]
Total	390
Commonwealth Edison Co
Debt Instrument [Line Items]
2024	250
2025	0
2026	500
2027	350
2028	550
Thereafter	10,167
Total	11,817
Commonwealth Edison Co \| ComEd Financing III Affiliate \| Long-term debt to financing trusts
Debt Instrument [Line Items]
Total	206
PECO Energy Co
Debt Instrument [Line Items]
2024	0
2025	350
2026	0
2027	0
2028	81
Thereafter	4,953
Total	5,384
PECO Energy Co \| PECO Financing Trusts \| Long-term debt to financing trusts
Debt Instrument [Line Items]
Total	184
Baltimore Gas and Electric Company
Debt Instrument [Line Items]
2024	0
2025	0
2026	350
2027	0
2028	0
Thereafter	4,300
Total	4,650
Pepco Holdings LLC
Debt Instrument [Line Items]
2024	644
2025	166
2026	15
2027	22
2028	358
Thereafter	7,070
Total	8,275
Potomac Electric Power Company
Debt Instrument [Line Items]
2024	405
2025	6
2026	5
2027	4
2028	3
Thereafter	3,728
Total	4,151
Delmarva Power & Light Company
Debt Instrument [Line Items]
2024	84
2025	6
2026	6
2027	15
2028	3
Thereafter	1,982
Total	2,096
Atlantic City Electric Company
Debt Instrument [Line Items]
2024	154
2025	154
2026	4
2027	3
2028	352
Thereafter	1,175
Total	$ 1,842

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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