Segment Information - Reconciliation to Consolidated Financial Statements (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Revenues	$ 19,078	$ 17,938	$ 16,663
Depreciation and amortization	3,325	3,033	2,891
Operating Expenses	15,761	15,256	14,485
Interest expense, net	1,447	1,289	1,307
Income taxes	349	38	(7)
Net income (loss)	2,171	1,829	1,954
Capital expenditures	7,147	7,981	8,048
Total assets	95,349	133,013
PECO Energy Co [Member]
Segment Reporting Information [Line Items]
Revenues	3,903	3,198	3,058
Operating revenues from affiliates	7	21	9
Income taxes	79	12	(30)
Net income (loss)	576	504	447
Capital expenditures	1,349	1,240	1,147
Total assets	14,502	13,824
Pepco Holdings LLC [Member]
Segment Reporting Information [Line Items]
Revenues	5,565	5,041	4,663
Operating revenues from affiliates	10	13	17
Income taxes	9	42	(77)
Net income (loss)	608	561	495
Capital expenditures	1,709	1,720	1,604
Total assets	26,082	24,744
Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	19,078	17,938	16,663
Net income (loss)	2,054	1,616	1,099
Capital expenditures	6,921	6,640	6,289
Total assets	95,349	86,669
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Income taxes	(21)	(48)	11
Net income (loss)	2,170	1,706	1,963
Total assets	40,578	47,989
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	(1,869)	(2,261)	(2,095)
Operating revenues from affiliates	6	57	23
Depreciation and amortization	0	1	0
Operating Expenses	(1,762)	(1,587)	(1,502)
Interest expense, net	(3)	(1)	(3)
Income taxes	(11)	(161)	(153)
Net income (loss)	(34)	(443)	(446)
Capital expenditures	0	0	0
Total assets	(4,260)	(8,319)
Intersegment Eliminations [Member] | Pepco Holdings LLC [Member]
Segment Reporting Information [Line Items]
Revenues	(383)	(380)	(374)
Operating revenues from affiliates	(383)	(381)	(375)
Depreciation and amortization	0	0	0
Operating Expenses	(383)	(381)	(375)
Interest expense, net	1	0	0
Income taxes	0	0	0
Net income (loss)	0	0	0
Capital expenditures	0	0	0
Total assets	(33)	(60)
Commonwealth Edison Co [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	5,761	6,406	5,904
Depreciation and amortization	1,323	1,205	1,133
Operating Expenses	4,218	5,151	4,950
Interest expense, net	414	389	382
Income taxes	264	172	177
Net income (loss)	917	742	438
Capital expenditures	2,506	2,387	2,217
Total assets	39,661	36,470
Commonwealth Edison Co [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Operating revenues from affiliates	16	41	37
PECO Energy Co [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	3,903	3,198	3,058
Depreciation and amortization	373	348	347
Operating Expenses	3,102	2,547	2,512
Interest expense, net	177	161	147
Income taxes	79	12	(30)
Net income (loss)	576	504	447
Capital expenditures	1,349	1,240	1,147
Total assets	14,502	13,824
PECO Energy Co [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Operating revenues from affiliates	7	21	9
Baltimore Gas and Electric Company [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	3,895	3,341	3,098
Depreciation and amortization	630	591	550
Operating Expenses	3,376	2,860	2,598
Interest expense, net	152	138	133
Income taxes	8	(35)	41
Net income (loss)	380	408	349
Capital expenditures	1,262	1,226	1,247
Total assets	13,350	12,324
Baltimore Gas and Electric Company [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Operating revenues from affiliates	15	31	20
Pepco Holdings LLC [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	5,565	5,041	4,663
Depreciation and amortization	938	821	782
Operating Expenses	4,734	4,240	4,045
Interest expense, net	292	267	268
Income taxes	9	42	(77)
Net income (loss)	608	561	495
Capital expenditures	1,709	1,720	1,604
Total assets	26,082	24,744
Pepco Holdings LLC [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Operating revenues from affiliates	10	13	17
Potomac Electric Power Company [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	2,531	2,274	2,149
Depreciation and amortization	417	403	377
Operating Expenses	2,140	1,871	1,799
Interest expense, net	150	140	138
Income taxes	(9)	15	(7)
Net income (loss)	305	296	266
Capital expenditures	874	843	773
Total assets	10,657	9,903
Potomac Electric Power Company [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Operating revenues from affiliates	5	5	7
Delmarva Power & Light Company [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	1,595	1,380	1,271
Depreciation and amortization	232	210	191
Operating Expenses	1,359	1,161	1,120
Interest expense, net	66	61	61
Income taxes	14	42	(25)
Net income (loss)	169	128	125
Capital expenditures	430	429	424
Total assets	5,802	5,412
Delmarva Power & Light Company [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Operating revenues from affiliates	6	7	9
Atlantic City Electric Company [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	1,431	1,388	1,245
Depreciation and amortization	261	179	180
Operating Expenses	1,225	1,201	1,123
Interest expense, net	66	58	59
Income taxes	3	(13)	(41)
Net income (loss)	148	146	112
Capital expenditures	398	445	401
Total assets	4,979	4,556
Atlantic City Electric Company [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Operating revenues from affiliates	2	2	4
Corporate and Other [Member] | Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Revenues	1,823	2,213	2,035
Depreciation and amortization	61	67	79
Operating Expenses	2,093	2,045	1,882
Interest expense, net	415	335	380
Income taxes	0	8	35
Net income (loss)	(393)	(156)	(184)
Capital expenditures	95	67	74
Total assets	6,014	7,626
Corporate and Other [Member] | Corporate, Non-Segment [Member] | Pepco Holdings LLC [Member]
Segment Reporting Information [Line Items]
Revenues	391	379	372
Depreciation and amortization	28	29	34
Operating Expenses	393	388	378
Interest expense, net	9	8	10
Income taxes	1	(2)	(4)
Net income (loss)	(14)	(9)	(8)
Capital expenditures	7	3	6
Total assets	4,677	4,933
Corporate and Other [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Operating revenues from affiliates	1,823	2,203	2,024
Corporate and Other [Member] | Intersegment Eliminations [Member] | Pepco Holdings LLC [Member]
Segment Reporting Information [Line Items]
Operating revenues from affiliates	380	380	372
Segment Elimination [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Operating revenues from affiliates	(1,865)	(2,252)	(2,084)
Electricity, US Regulated [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	16,899	16,245	15,236
Electricity, US Regulated [Member] | PECO Energy Co [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	3,156	2,613	2,519
Electricity, US Regulated [Member] | Pepco Holdings LLC [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	5,376	4,769	4,463
Electricity, US Regulated [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	17,083	16,395	15,224
Electricity, US Regulated [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	(31)	(35)	(44)
Electricity, US Regulated [Member] | Intersegment Eliminations [Member] | Pepco Holdings LLC [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	(2)	(14)	(18)
Electricity, US Regulated [Member] | Commonwealth Edison Co [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	5,761	6,406	5,904
Electricity, US Regulated [Member] | PECO Energy Co [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	3,165	2,659	2,543
Electricity, US Regulated [Member] | Baltimore Gas and Electric Company [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	2,871	2,505	2,336
Electricity, US Regulated [Member] | Pepco Holdings LLC [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	5,317	4,860	4,485
Electricity, US Regulated [Member] | Potomac Electric Power Company [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	2,531	2,274	2,149
Electricity, US Regulated [Member] | Delmarva Power & Light Company [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	1,357	1,212	1,109
Electricity, US Regulated [Member] | Atlantic City Electric Company [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	1,431	1,388	1,245
Electricity, US Regulated [Member] | Corporate and Other [Member] | Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	0	0	0
Electricity, US Regulated [Member] | Corporate and Other [Member] | Corporate, Non-Segment [Member] | Pepco Holdings LLC [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	0	0	0
Natural Gas, US Regulated [Member] | PECO Energy Co [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	738	538	514
Natural Gas, US Regulated [Member] | Pepco Holdings LLC [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	238	168	162
Natural Gas, US Regulated [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	1,995	1,543	1,439
Natural Gas, US Regulated [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	(5)	0	0
Natural Gas, US Regulated [Member] | Intersegment Eliminations [Member] | Pepco Holdings LLC [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	0	0	0
Natural Gas, US Regulated [Member] | Commonwealth Edison Co [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	0	0	0
Natural Gas, US Regulated [Member] | PECO Energy Co [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	738	539	515
Natural Gas, US Regulated [Member] | Baltimore Gas and Electric Company [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	1,024	836	762
Natural Gas, US Regulated [Member] | Pepco Holdings LLC [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	238	168	162
Natural Gas, US Regulated [Member] | Potomac Electric Power Company [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	0	0	0
Natural Gas, US Regulated [Member] | Delmarva Power & Light Company [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	238	168	162
Natural Gas, US Regulated [Member] | Atlantic City Electric Company [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	0	0	0
Natural Gas, US Regulated [Member] | Corporate and Other [Member] | Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	0	0	0
Natural Gas, US Regulated [Member] | Corporate and Other [Member] | Corporate, Non-Segment [Member] | Pepco Holdings LLC [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	0	0	0
Service, Other [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	0	0	0
Service, Other [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	(1,833)	(2,226)	(2,051)
Service, Other [Member] | Intersegment Eliminations [Member] | Pepco Holdings LLC [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	(381)	(366)	(356)
Service, Other [Member] | Commonwealth Edison Co [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	0	0	0
Service, Other [Member] | PECO Energy Co [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	0	0	0
Service, Other [Member] | Baltimore Gas and Electric Company [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	0	0	0
Service, Other [Member] | Pepco Holdings LLC [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	10	13	16
Service, Other [Member] | Potomac Electric Power Company [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	0	0	0
Service, Other [Member] | Delmarva Power & Light Company [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	0	0	0
Service, Other [Member] | Atlantic City Electric Company [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	0	0	0
Service, Other [Member] | Corporate and Other [Member] | Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	1,823	2,213	2,035
Service, Other [Member] | Corporate and Other [Member] | Corporate, Non-Segment [Member] | Pepco Holdings LLC [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 391	$ 379	$ 372