Financial Information by Business Segment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Cost of services provided	$ 14,663	$ 15,670	$ 13,676
Depreciation and amortization	2,031	2,056	2,032
Operating income	3,196	2,624	2,826
Other Income (deductions)	830	326	(538)
Interest charges	1,023	852	905
Income Tax Expense	487	498	190
Total assets	66,331	69,065	63,116
Capital expenditures	4,509	4,465	3,964
CECONY
Segment Reporting Information [Line Items]
Cost of services provided	13,476	13,268	11,716
Depreciation and amortization	1,924	1,778	1,705
Operating income	2,177	2,135	2,460
Other Income (deductions)	732	332	(108)
Total assets	61,600	57,445
Operating segment | Clean Energy Businesses
Segment Reporting Information [Line Items]
Cost of services provided	129	1,319	1,022
Depreciation and amortization	0	178	231
Operating income	37	368	236
Other Income (deductions)	1	3	(10)
Interest charges	16	(35)	68
Income Tax Expense	3	84	44
Total assets	0	7,224	6,554
Capital expenditures	81	399	298
Operating segment | Con Edison Transmission
Segment Reporting Information [Line Items]
Cost of services provided	4	4	4
Depreciation and amortization	1	1	1
Operating income	(9)	(10)	(16)
Other Income (deductions)	62	19	(407)
Interest charges	2	5	9
Income Tax Expense	14	5	(114)
Total assets	414	314	249
Capital expenditures	49	65	31
Operating segment | CECONY
Segment Reporting Information [Line Items]
Cost of services provided	13,476	13,268	11,716
Depreciation and amortization	1,924	1,778	1,705
Operating income	2,177	2,135	2,460
Other Income (deductions)	732	332	(108)
Interest charges	945	822	762
Income Tax Expense	358	255	246
Total assets	61,600	57,445	52,655
Capital expenditures	4,083	3,758	3,418
Operating segment | CECONY | Electric
Segment Reporting Information [Line Items]
Cost of services provided	10,078	9,751	8,806
Depreciation and amortization	1,395	1,315	1,286
Operating income	1,568	1,496	1,802
Other Income (deductions)	564	259	(84)
Interest charges	674	582	542
Income Tax Expense	217	134	146
Total assets	42,226	39,153	36,260
Capital expenditures	2,909	2,522	2,189
Operating segment | CECONY | Gas
Segment Reporting Information [Line Items]
Cost of services provided	2,829	2,924	2,378
Depreciation and amortization	429	367	326
Operating income	682	660	646
Other Income (deductions)	122	52	(16)
Interest charges	227	198	179
Income Tax Expense	159	140	109
Total assets	16,343	15,361	13,748
Capital expenditures	1,046	1,128	1,126
Operating segment | CECONY | Steam
Segment Reporting Information [Line Items]
Cost of services provided	569	593	532
Depreciation and amortization	100	96	93
Operating income	(73)	(21)	12
Other Income (deductions)	46	21	(8)
Interest charges	44	42	41
Income Tax Expense	(18)	(19)	(9)
Total assets	3,031	2,931	2,647
Capital expenditures	128	108	103
Operating segment | O&R
Segment Reporting Information [Line Items]
Cost of services provided	1,056	1,085	941
Depreciation and amortization	106	98	95
Operating income	126	136	150
Other Income (deductions)	49	23	(12)
Interest charges	51	46	42
Income Tax Expense	28	25	21
Total assets	3,675	3,511	3,292
Capital expenditures	296	243	217
Operating segment | O&R | Electric
Segment Reporting Information [Line Items]
Cost of services provided	759	773	681
Depreciation and amortization	76	71	69
Operating income	85	94	100
Other Income (deductions)	37	17	(8)
Interest charges	32	29	27
Income Tax Expense	20	17	14
Total assets	2,329	2,247	2,123
Capital expenditures	211	167	147
Operating segment | O&R | Gas
Segment Reporting Information [Line Items]
Cost of services provided	297	312	260
Depreciation and amortization	30	27	26
Operating income	41	42	50
Other Income (deductions)	12	6	(4)
Interest charges	19	17	15
Income Tax Expense	8	8	7
Total assets	1,346	1,264	1,169
Capital expenditures	85	76	70
Other
Segment Reporting Information [Line Items]
Cost of services provided	(2)	(6)	(7)
Depreciation and amortization	0	1	0
Operating income	865	(5)	(4)
Other Income (deductions)	(14)	(51)	(1)
Interest charges	9	14	24
Income Tax Expense	84	129	(7)
Total assets	642	571	366
Capital expenditures	0	0	0
Inter- segment revenues | CECONY
Segment Reporting Information [Line Items]
Cost of services provided	(100)	(103)	(100)
Inter- segment revenues | CECONY | Electric
Segment Reporting Information [Line Items]
Cost of services provided	18	19	18
Inter- segment revenues | CECONY | Gas
Segment Reporting Information [Line Items]
Cost of services provided	8	8	8
Inter- segment revenues | CECONY | Steam
Segment Reporting Information [Line Items]
Cost of services provided	$ 74	$ 76	$ 74