Consolidated Statements of Operations and Comprehensive Income (Unaudited) - USD ($) shares in Millions, $ in Millions		3 Months Ended
		Mar. 31, 2022	Mar. 31, 2021
Operating revenues
Revenues from alternative revenue programs		$ 29	$ 129
Operating revenues from affiliates		6	7
Total operating revenues		5,327	4,632
Operating expenses
Purchased power and/or fuel from affiliates		159	293
Operating and maintenance		1,178	1,083
Depreciation and amortization		817	757
Taxes other than income taxes		354	317
Total operating expenses		4,427	3,808
Operating income (loss)		900	824
Other income and (deductions)
Interest expense, net		(332)	(312)
Interest expense to affiliates		(6)	(6)
Other, net		137	58
Total other deductions		(201)	(260)
Income (Loss) before income taxes		699	564
Income taxes		218	39
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest		481	525
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest		117	(789)
Net income (loss)		598	(264)
Net income (loss) attributable to noncontrolling interests		1	25
Net Income (Loss) Available to Common Stockholders, Basic		597	(289)
Net Income (Loss) from Continuing Operations Available to Common Shareholders, Basic		481	525
Net Income (Loss) from Discontinued Operations Available to Common Shareholders, Basic		116	(814)
Other comprehensive income (loss), net of income taxes
Prior service benefit reclassified to periodic benefit cost		0	(1)
Actuarial loss reclassified to periodic benefit cost		14	56
Pension and non-pension postretirement benefit plan valuation adjustment		0	(2)
Unrealized gain (loss) on foreign currency translation		0	1
Other comprehensive income		14	54
Comprehensive income		612	(210)
Comprehensive income attributable to noncontrolling interests		1	25
Comprehensive income attributable to common shareholders/membership interest		$ 611	$ (235)
Average shares of common stock outstanding:
Basic average shares of common stock outstanding		981	977
Assumed exercise and/or distributions of stock-based awards		0	1
Diluted average shares of common stock outstanding	[1]	981	978
Earnings per average common share from continuing operations
Income (Loss) from Continuing Operations, Per Basic Share		$ 0.49	$ 0.53
Income (Loss) from Continuing Operations, Per Diluted Share		0.49	0.53
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share		0.12	(0.83)
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Diluted Share		$ 0.12	$ (0.83)
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount			1
Commonwealth Edison Co [Member]
Operating revenues
Revenues from alternative revenue programs		$ 40	$ 54
Operating revenues from affiliates		6	6
Total operating revenues		1,734	1,535
Operating expenses
Purchased power and/or fuel from affiliates		59	85
Operating and maintenance		266	245
Related Party Transaction, Expenses from Transactions with Related Party		85	71
Depreciation and amortization		321	292
Taxes other than income taxes		96	75
Total operating expenses		1,406	1,210
Operating income (loss)		328	325
Other income and (deductions)
Interest expense, net		(97)	(93)
Interest expense to affiliates		(3)	(3)
Other, net		12	7
Total other deductions		(88)	(89)
Income (Loss) before income taxes		240	236
Income taxes		52	39
Net income (loss)		188	197
Other comprehensive income (loss), net of income taxes
Comprehensive income		188	197
PECO Energy Co [Member]
Operating revenues
Revenues from alternative revenue programs		6	10
Operating revenues from affiliates		1	2
Total operating revenues		1,047	889
Operating expenses
Purchased power and/or fuel from affiliates		33	41
Operating and maintenance		196	193
Related Party Transaction, Expenses from Transactions with Related Party		51	41
Depreciation and amortization		92	86
Taxes other than income taxes		47	43
Total operating expenses		793	679
Operating income (loss)		254	210
Other income and (deductions)
Interest expense, net		(38)	(35)
Interest expense to affiliates		(3)	(3)
Other, net		7	5
Total other deductions		(34)	(33)
Income (Loss) before income taxes		220	177
Income taxes		14	10
Net income (loss)		206	167
Other comprehensive income (loss), net of income taxes
Comprehensive income		206	167
Baltimore Gas and Electric Company [Member]
Operating revenues
Revenues from alternative revenue programs		(12)	18
Operating revenues from affiliates		7	6
Total operating revenues		1,154	974
Operating expenses
Purchased power and/or fuel from affiliates		18	70
Operating and maintenance		167	152
Related Party Transaction, Expenses from Transactions with Related Party		51	45
Depreciation and amortization		171	152
Taxes other than income taxes		76	72
Total operating expenses		919	752
Operating income (loss)		235	222
Other income and (deductions)
Interest expense, net		(35)	(34)
Other, net		7	8
Total other deductions		(28)	(26)
Income (Loss) before income taxes		207	196
Income taxes		9	(13)
Net income (loss)		198	209
Other comprehensive income (loss), net of income taxes
Comprehensive income		198	209
Pepco Holdings LLC [Member]
Operating revenues
Revenues from alternative revenue programs		(5)	46
Operating revenues from affiliates		3	3
Total operating revenues		1,404	1,244
Operating expenses
Purchased power and/or fuel from affiliates		50	98
Operating and maintenance		248	216
Related Party Transaction, Expenses from Transactions with Related Party		51	40
Depreciation and amortization		218	210
Taxes other than income taxes		119	113
Total operating expenses		1,215	1,058
Operating income (loss)		189	186
Other income and (deductions)
Interest expense, net		(69)	(67)
Other, net		17	17
Total other deductions		(52)	(50)
Income (Loss) before income taxes		137	136
Income taxes		7	8
Net income (loss)		130	128
Other comprehensive income (loss), net of income taxes
Comprehensive income attributable to common shareholders/membership interest		130	128
Potomac Electric Power Company [Member]
Operating revenues
Revenues from alternative revenue programs		(7)	26
Operating revenues from affiliates		1	1
Total operating revenues		614	553
Operating expenses
Purchased power and/or fuel from affiliates		39	74
Operating and maintenance		73	56
Related Party Transaction, Expenses from Transactions with Related Party		58	52
Depreciation and amortization		108	102
Taxes other than income taxes		95	90
Total operating expenses		547	466
Operating income (loss)		67	87
Other income and (deductions)
Interest expense, net		(36)	(34)
Other, net		13	12
Total other deductions		(23)	(22)
Income (Loss) before income taxes		44	65
Income taxes		(2)	6
Net income (loss)		46	59
Other comprehensive income (loss), net of income taxes
Comprehensive income		46	59
Delmarva Power and Light Company [Member]
Operating revenues
Revenues from alternative revenue programs		(1)	9
Operating revenues from affiliates		1	2
Total operating revenues		431	382
Operating expenses
Purchased power and/or fuel from affiliates		10	20
Operating and maintenance		51	44
Related Party Transaction, Expenses from Transactions with Related Party		42	39
Depreciation and amortization		57	53
Taxes other than income taxes		18	17
Total operating expenses		357	309
Operating income (loss)		74	73
Other income and (deductions)
Interest expense, net		(16)	(15)
Other, net		2	3
Total other deductions		(14)	(12)
Income (Loss) before income taxes		60	61
Income taxes		4	5
Net income (loss)		56	56
Other comprehensive income (loss), net of income taxes
Comprehensive income		56	56
Atlantic City Electric Company [Member]
Operating revenues
Revenues from alternative revenue programs		3	11
Operating revenues from affiliates		1	1
Total operating revenues		349	310
Operating expenses
Purchased power and/or fuel from affiliates		2	4
Operating and maintenance		47	42
Related Party Transaction, Expenses from Transactions with Related Party		37	34
Depreciation and amortization		47	47
Taxes other than income taxes		2	2
Total operating expenses		311	282
Operating income (loss)		38	28
Other income and (deductions)
Interest expense, net		(14)	(15)
Other, net		3	1
Total other deductions		(11)	(14)
Income (Loss) before income taxes		27	14
Income taxes		1	0
Net income (loss)		26	14
Other comprehensive income (loss), net of income taxes
Comprehensive income		26	14
Generation commodities and services
Operating revenues
Revenue from Contract with Customer, Including Assessed Tax		4,481	3,870
Operating expenses
Purchased power and/or fuel		1,581	1,140
Natural gas operating revenues
Operating revenues
Revenue from Contract with Customer, Including Assessed Tax		817	633
Operating expenses
Purchased power and/or fuel		338	218
Electricity, US Regulated
Operating revenues
Revenue from Contract with Customer, Including Assessed Tax		4,522	3,991
Electricity, US Regulated | Commonwealth Edison Co [Member]
Operating revenues
Revenue from Contract with Customer, Including Assessed Tax		1,688	1,475
Operating expenses
Purchased power and/or fuel		579	442
Electricity, US Regulated | PECO Energy Co [Member]
Operating revenues
Revenue from Contract with Customer, Including Assessed Tax		734	649
Operating expenses
Purchased power and/or fuel		229	189
Electricity, US Regulated | Baltimore Gas and Electric Company [Member]
Operating revenues
Revenue from Contract with Customer, Including Assessed Tax		735	620
Operating expenses
Purchased power and/or fuel		285	162
Electricity, US Regulated | Pepco Holdings LLC [Member]
Operating revenues
Revenue from Contract with Customer, Including Assessed Tax		1,323	1,124
Operating expenses
Purchased power and/or fuel		487	348
Electricity, US Regulated | Potomac Electric Power Company [Member]
Operating revenues
Revenue from Contract with Customer, Including Assessed Tax		620	526
Operating expenses
Purchased power and/or fuel		174	92
Electricity, US Regulated | Delmarva Power and Light Company [Member]
Operating revenues
Revenue from Contract with Customer, Including Assessed Tax		348	300
Operating expenses
Purchased power and/or fuel		137	103
Electricity, US Regulated | Atlantic City Electric Company [Member]
Operating revenues
Revenue from Contract with Customer, Including Assessed Tax		345	298
Operating expenses
Purchased power and/or fuel		176	153
Natural Gas, US Regulated
Operating revenues
Revenue from Contract with Customer, Including Assessed Tax		805	641
Natural Gas, US Regulated | PECO Energy Co [Member]
Operating revenues
Revenue from Contract with Customer, Including Assessed Tax		306	228
Operating expenses
Purchased power and/or fuel		145	86
Natural Gas, US Regulated | Baltimore Gas and Electric Company [Member]
Operating revenues
Revenue from Contract with Customer, Including Assessed Tax		424	330
Operating expenses
Purchased power and/or fuel		151	99
Natural Gas, US Regulated | Pepco Holdings LLC [Member]
Operating revenues
Revenue from Contract with Customer, Including Assessed Tax		83	71
Operating expenses
Purchased power and/or fuel		42	33
Natural Gas, US Regulated | Delmarva Power and Light Company [Member]
Operating revenues
Revenue from Contract with Customer, Including Assessed Tax		83	71
Operating expenses
Purchased power and/or fuel		$ 42	$ 33

[1] The number of stock options not included in the calculation of diluted common shares outstanding due to their antidilutive effect were none and less than 1 million for the three months ended March 31, 2022 and 2021, respectively