v3.26.1
Regulatory Matters - Regulatory Assets (Details) - USD ($)
$ in Millions
Jun. 30, 2026
Dec. 31, 2025
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent $ 5,681.0 $ 5,599.0
Regulatory assets – current 271.0 103.0
Total Regulatory Assets 5,952.0 5,702.0
Energy efficiency and other clean energy programs    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 2,095.0 1,994.0
Environmental investigation and remediation costs    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 1,079.0 1,079.0
Customer account deferrals    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 997.0 1,089.0
Revenue taxes    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 680.0 638.0
Legacy meters    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 372.0 382.0
Property tax reconciliation    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 121.0 101.0
Deferred storm costs    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 78.0 85.0
Deferred derivative losses - long term    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 24.0 18.0
Pension and other postretirement employee benefits deferrals    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 18.0 0.0
Unrecognized pension and other postretirement costs    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 7.0 4.0
Other    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 210.0 209.0
Recoverable energy costs    
Regulatory Assets [Line Items]    
Regulatory assets – current 184.0 6.0
Deferred derivative losses - short term    
Regulatory Assets [Line Items]    
Regulatory assets – current 87.0 97.0
CECONY    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 5,294.0 5,235.0
Regulatory assets – current 264.0 95.0
CECONY | Subsidiaries    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 5,294.0 5,235.0
Regulatory assets – current 264.0 95.0
Total Regulatory Assets 5,558.0 5,330.0
CECONY | Energy efficiency and other clean energy programs | Subsidiaries    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 1,982.0 1,893.0
CECONY | Environmental investigation and remediation costs | Subsidiaries    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 988.0 987.0
CECONY | Customer account deferrals | Subsidiaries    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 993.0 1,084.0
CECONY | Revenue taxes | Subsidiaries    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 650.0 611.0
CECONY | Legacy meters | Subsidiaries    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 360.0 370.0
CECONY | Property tax reconciliation | Subsidiaries    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 111.0 97.0
CECONY | Deferred storm costs | Subsidiaries    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 12.0 1.0
CECONY | Deferred derivative losses - long term | Subsidiaries    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 23.0 15.0
CECONY | Pension and other postretirement employee benefits deferrals | Subsidiaries    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 0.0 0.0
CECONY | Unrecognized pension and other postretirement costs | Subsidiaries    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 0.0 0.0
CECONY | Other | Subsidiaries    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 175.0 177.0
CECONY | Recoverable energy costs | Subsidiaries    
Regulatory Assets [Line Items]    
Regulatory assets – current 184.0 5.0
CECONY | Deferred derivative losses - short term | Subsidiaries    
Regulatory Assets [Line Items]    
Regulatory assets – current 80.0 90.0
CECONY | Arrears Relief Program Deferral    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent 227.7 262.9
O&R | Arrears Relief Program Deferral    
Regulatory Assets [Line Items]    
Regulatory assets – noncurrent $ 0.0 $ 0.8