Leases - Schedule of Future Minimum Lease Payments (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Operating Leases
2026	$ 73
2027	71
2028	66
2029	67
2030	64
All years thereafter	291
Total future minimum lease payments	632
Less: imputed interest	(132)
Total	500
Operating lease liabilities (current)	123	$ 118
Operating lease liabilities (noncurrent)	377	386
Total	500
Finance Leases
2026	1
2027	1
2028	1
2029	0
2030	0
All years thereafter	0
Total future minimum lease payments	3
Less: imputed interest	0
Total	3
Other current liabilities	1
Other noncurrent liabilities	2
Total	$ 3
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other current liabilities
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other deferred credits and noncurrent liabilities
CECONY
Operating Leases
2026	$ 72
2027	71
2028	66
2029	67
2030	64
All years thereafter	291
Total future minimum lease payments	631
Less: imputed interest	(132)
Total	499
Operating lease liabilities (current)	122	118
Operating lease liabilities (noncurrent)	377	$ 386
Total	499
Finance Leases
2026	1
2027	1
2028	0
2029	0
2030	0
All years thereafter	0
Total future minimum lease payments	2
Less: imputed interest	0
Total	2
Other current liabilities	1
Other noncurrent liabilities	1
Total	$ 2
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other current liabilities
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other deferred credits and noncurrent liabilities