Related Party Transactions - Utility Registrants' expense with Generation (Details) - Exelon Generation Co L L C [Member] $ in Millions	6 Months Ended
	Jun. 30, 2022 USD ($)
Commonwealth Edison Co Affiliate [Member]
Related Party Transaction [Line Items]
Revenues from Related Parties	$ 59
PECO Energy Co Affiliate [Member]
Related Party Transaction [Line Items]
Revenues from Related Parties	33
Baltimore Gas And Electric Company Affiliate [Member]
Related Party Transaction [Line Items]
Revenues from Related Parties	18
Pepco Holdings LLC Affiliate [Member]
Related Party Transaction [Line Items]
Revenues from Related Parties	51
Potomac Electric Power Co Affiliate [Member]
Related Party Transaction [Line Items]
Revenues from Related Parties	39
Delmarva Power and Light Co Affiliate [Member]
Related Party Transaction [Line Items]
Revenues from Related Parties	10
Atlantic City Electric Co Affiliate [Member]
Related Party Transaction [Line Items]
Revenues from Related Parties	$ 2