Leases - Future Minimum Lease Payments (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Operating Leases
2023	$ 84
2024	77
2025	78
2026	78
2027	76
All years thereafter	871
Total future minimum lease payments	1,264
Less: imputed interest	(428)
Total	836
Operating lease liabilities (current)	120	$ 113
Operating lease liabilities (noncurrent)	716	717
Total	836
Finance Leases
2023	0
2024	0
2025	1
2026	0
2027	0
All years thereafter	1
Total future minimum lease payments	2
Less: imputed interest	0
Other noncurrent liabilities	2
Total	2
Subsidiaries
Operating Leases
Operating lease liabilities (current)	92	90
Operating lease liabilities (noncurrent)	465	$ 462
CECONY | Subsidiaries
Operating Leases
2023	60
2024	59
2025	59
2026	60
2027	60
All years thereafter	394
Total future minimum lease payments	692
Less: imputed interest	(135)
Total	557
Operating lease liabilities (current)	92
Operating lease liabilities (noncurrent)	465
Total	557
Finance Leases
2023	0
2024	0
2025	1
2026	0
2027	0
All years thereafter	0
Total future minimum lease payments	1
Less: imputed interest	0
Other noncurrent liabilities	1
Total	$ 1