Schedule II - Valuation and Qualifying Accounts Schedule (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
SEC Schedule, 12-09, Allowance, Credit Loss [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 392	$ 405	$ 213
Charged to Costs and Expenses	174	107	228
Charged to Other Accounts	28	0	38
Deductions	185	120	74
Balance at End of Period	409	392	405
Deferred Tax Valuation Allowance [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	37	4	2
Charged to Costs and Expenses	0	0	0
Charged to Other Accounts	57	33	2
Deductions	0	0	0
Balance at End of Period	94	37	4
Reserve for Obsolete Materials [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	13	11	12
Charged to Costs and Expenses	8	5	5
Charged to Other Accounts	0	0	0
Deductions	6	3	6
Balance at End of Period	15	13	11
SEC Schedule, 12-09, Allowance, Notes Receivable [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	14	5
Balance at End of Period	7	14	5
Commonwealth Edison Co [Member] | SEC Schedule, 12-09, Allowance, Credit Loss [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	90	118	79
Charged to Costs and Expenses	24	18	54
Charged to Other Accounts	8	1	13
Deductions	46	47	28
Balance at End of Period	76	90	118
Commonwealth Edison Co [Member] | Reserve for Obsolete Materials [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	7	6	7
Charged to Costs and Expenses	5	3	3
Charged to Other Accounts	0	0	0
Deductions	4	2	4
Balance at End of Period	8	7	6
PECO Energy Co [Member] | SEC Schedule, 12-09, Allowance, Credit Loss [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	112	124	62
Charged to Costs and Expenses	44	32	76
Charged to Other Accounts	14	(6)	6
Deductions	56	38	20
Balance at End of Period	114	112	124
PECO Energy Co [Member] | Deferred Tax Valuation Allowance [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	3	1	0
Charged to Costs and Expenses	0	0	0
Charged to Other Accounts	4	2	1
Deductions	0	0	0
Balance at End of Period	7	3	1
PECO Energy Co [Member] | Reserve for Obsolete Materials [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	2	2	2
Charged to Costs and Expenses	2	1	1
Charged to Other Accounts	0	0	0
Deductions	1	1	1
Balance at End of Period	3	2	2
PECO Energy Co [Member] | SEC Schedule, 12-09, Allowance, Notes Receivable [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	14	5
Balance at End of Period	7	14	5
Baltimore Gas and Electric Company [Member] | SEC Schedule, 12-09, Allowance, Credit Loss [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	47	44	17
Charged to Costs and Expenses	37	16	31
Charged to Other Accounts	6	3	6
Deductions	26	16	10
Balance at End of Period	64	47	44
Baltimore Gas and Electric Company [Member] | Deferred Tax Valuation Allowance [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	0	0	1
Charged to Costs and Expenses	0		0
Charged to Other Accounts	3		(1)
Deductions	0		0
Balance at End of Period	3	0	0
Baltimore Gas and Electric Company [Member] | Reserve for Obsolete Materials [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	1	1	1
Charged to Costs and Expenses	1	0	0
Charged to Other Accounts	0	0	0
Deductions	0	0	0
Balance at End of Period	2	1	1
Pepco Holdings LLC [Member] | SEC Schedule, 12-09, Allowance, Credit Loss [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	143	119	53
Charged to Costs and Expenses	69	41	69
Charged to Other Accounts	0	2	13
Deductions	57	19	16
Balance at End of Period	155	143	119
Pepco Holdings LLC [Member] | Deferred Tax Valuation Allowance [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	31	0
Charged to Costs and Expenses	0	0
Charged to Other Accounts	4	31
Deductions	0	0
Balance at End of Period	35	31	0
Pepco Holdings LLC [Member] | Reserve for Obsolete Materials [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	3	2	3
Charged to Costs and Expenses	0	1	0
Charged to Other Accounts	0	0	0
Deductions	1	0	1
Balance at End of Period	2	3	2
Potomac Electric Power Company [Member] | SEC Schedule, 12-09, Allowance, Credit Loss [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	53	45	20
Charged to Costs and Expenses	36	14	25
Charged to Other Accounts	4	2	5
Deductions	21	8	5
Balance at End of Period	72	53	45
Potomac Electric Power Company [Member] | Reserve for Obsolete Materials [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	1	1	1
Charged to Costs and Expenses	0	0	0
Charged to Other Accounts	0	0	0
Deductions	0	0	0
Balance at End of Period	1	1	1
Delmarva Power & Light Company [Member] | SEC Schedule, 12-09, Allowance, Credit Loss [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	26	31	15
Charged to Costs and Expenses	13	6	16
Charged to Other Accounts	(2)	(1)	4
Deductions	9	10	4
Balance at End of Period	28	26	31
Delmarva Power & Light Company [Member] | Deferred Tax Valuation Allowance [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	31	0
Charged to Costs and Expenses	0	0
Charged to Other Accounts	1	31
Deductions	0	0
Balance at End of Period	32	31	0
Atlantic City Electric Company [Member] | SEC Schedule, 12-09, Allowance, Credit Loss [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	64	43	18
Charged to Costs and Expenses	20	21	28
Charged to Other Accounts	(2)	1	4
Deductions	27	1	7
Balance at End of Period	55	64	43
Atlantic City Electric Company [Member] | Reserve for Obsolete Materials [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	1	0	1
Charged to Costs and Expenses	0	1	0
Charged to Other Accounts	0	0	0
Deductions	0	0	1
Balance at End of Period	$ 1	$ 1	$ 0