Environmental Matters - Schedule of Accrued Liabilities and Regulatory Assets (Details) - USD ($) $ in Millions |
Jun. 30, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Site Contingency [Line Items] | ||
| Total | $ 1,078 | $ 1,079 |
| Regulatory assets | 5,952 | 5,702 |
| Manufactured gas plant sites | ||
| Site Contingency [Line Items] | ||
| Total | 976 | 980 |
| Other Superfund Sites | ||
| Site Contingency [Line Items] | ||
| Total | 102 | 99 |
| Superfund Sites | ||
| Site Contingency [Line Items] | ||
| Total | 1,078 | 1,079 |
| Regulatory assets | 1,079 | 1,079 |
| CECONY | ||
| Site Contingency [Line Items] | ||
| Total | 980 | 980 |
| CECONY | Manufactured gas plant sites | ||
| Site Contingency [Line Items] | ||
| Total | 879 | 882 |
| CECONY | Other Superfund Sites | ||
| Site Contingency [Line Items] | ||
| Total | 101 | 98 |
| CECONY | Superfund Sites | ||
| Site Contingency [Line Items] | ||
| Total | 980 | 980 |
| Regulatory assets | $ 988 | $ 987 |