Schedule I - Condensed Financial Information of Parent (Exelon Corporate) - Related Party Transactions - Summary of Related Party Transactions (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Related Party Transaction [Line Items]
Other accounts receivable, net	$ 1,019	$ 1,344
Related Party
Related Party Transaction [Line Items]
Accounts payable	5	5
Corporate, Non-Segment
Related Party Transaction [Line Items]
Equity in earnings (losses) of investments	2,728	2,450	$ 1,908
Investments in affiliates	38,545	35,925
Corporate, Non-Segment \| Exelon Business Services Co Affiliate
Related Party Transaction [Line Items]
Operating and maintenance from affiliates	7	4	14
Interest expense to affiliates, net	6	4	0
Equity in earnings (losses) of investments	0	(18)	(301)
Receivable from affiliates	0	3
Other accounts receivable, net	160	138
Investments in affiliates	384	384
Accounts payable	1	0
Corporate, Non-Segment \| Commonwealth Edison Co
Related Party Transaction [Line Items]
Receivable from affiliates	4	4
Corporate, Non-Segment \| PECO Energy Co
Related Party Transaction [Line Items]
Receivable from affiliates	2	2
Corporate, Non-Segment \| Baltimore Gas and Electric Company
Related Party Transaction [Line Items]
Receivable from affiliates	1	1
Corporate, Non-Segment \| PHI Service Co Affiliate
Related Party Transaction [Line Items]
Receivable from affiliates	7	7
Corporate, Non-Segment \| Exelon Enterprise
Related Party Transaction [Line Items]
Equity in earnings (losses) of investments	1	0	0
Investments in affiliates	4	3
Corporate, Non-Segment \| Related Party
Related Party Transaction [Line Items]
Operating and maintenance from affiliates	7	4	14
Interest expense to affiliates, net	9	5	0
Contributions from member	1,978	2,027	1,842
Receivable from affiliates	14	17
Other accounts receivable, net	225	182
Accounts payable	361	360
Corporate, Non-Segment \| Pepco Holdings LLC Affiliate
Related Party Transaction [Line Items]
Other accounts receivable, net	65	44
Corporate, Non-Segment \| Exelon Energy Delivery Company LLC
Related Party Transaction [Line Items]
Interest expense to affiliates, net	3	1	0
Equity in earnings (losses) of investments	2,727	2,482	2,215
Investments in affiliates	37,705	35,092
Corporate, Non-Segment \| PCI
Related Party Transaction [Line Items]
Equity in earnings (losses) of investments	2	(9)	(1)
Investments in affiliates	54	52
Corporate, Non-Segment \| UII
Related Party Transaction [Line Items]
Investments in affiliates	365	365
Accounts payable	360	360
Corporate, Non-Segment \| Voluntary Employee Beneficiary Association trust
Related Party Transaction [Line Items]
Investments in affiliates	9	4
Corporate, Non-Segment \| Conectiv
Related Party Transaction [Line Items]
Investments in affiliates	12	12
Corporate, Non-Segment \| Exelon InQB8R
Related Party Transaction [Line Items]
Equity in earnings (losses) of investments	(2)	(4)	(7)
Investments in affiliates	13	15
Corporate, Non-Segment \| Other Affiliate
Related Party Transaction [Line Items]
Equity in earnings (losses) of investments	0	(1)	$ 2
Investments in affiliates	$ (1)	$ (2)

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