Related Party Transactions - Long Term Debt to Financing Trusts (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Related Party Transaction [Line Items]
Long-term debt to Financing Trusts	$ 390	$ 390
ComEd Financing Three Affiliate [Member]
Related Party Transaction [Line Items]
Long-term debt to Financing Trusts	206	206
PECO Trust Three Affiliate [Member]
Related Party Transaction [Line Items]
Long-term debt to Financing Trusts	81	81
PECO Trust Four Affiliate [Member]
Related Party Transaction [Line Items]
Long-term debt to Financing Trusts	103	103
Related Party
Related Party Transaction [Line Items]
Long-term debt to Financing Trusts	390	390
Commonwealth Edison Co [Member] | ComEd Financing Three Affiliate [Member]
Related Party Transaction [Line Items]
Long-term debt to Financing Trusts	205	205
Commonwealth Edison Co [Member] | PECO Trust Three Affiliate [Member]
Related Party Transaction [Line Items]
Long-term debt to Financing Trusts	0	0
Commonwealth Edison Co [Member] | PECO Trust Four Affiliate [Member]
Related Party Transaction [Line Items]
Long-term debt to Financing Trusts	0	0
Commonwealth Edison Co [Member] | Related Party
Related Party Transaction [Line Items]
Long-term debt to Financing Trusts	205	205
PECO Energy Co [Member] | ComEd Financing Three Affiliate [Member]
Related Party Transaction [Line Items]
Long-term debt to Financing Trusts	0	0
PECO Energy Co [Member] | PECO Trust Three Affiliate [Member]
Related Party Transaction [Line Items]
Long-term debt to Financing Trusts	81	81
PECO Energy Co [Member] | PECO Trust Four Affiliate [Member]
Related Party Transaction [Line Items]
Long-term debt to Financing Trusts	103	103
PECO Energy Co [Member] | Related Party
Related Party Transaction [Line Items]
Long-term debt to Financing Trusts	$ 184	$ 184