v3.26.1
Other Postretirement Benefits - Schedule of Periodic Postretirement Benefit Costs (Details) - Other Postretirement Benefits - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Defined Benefit Plan Disclosure [Line Items]        
Service cost - including administrative expenses $ 3 $ 3 $ 6 $ 6
Interest cost on projected other postretirement benefit obligation 12 12 23 24
Expected return on plan assets (16) (17) (32) (34)
Recognition of net actuarial gain (2) (7) (4) (13)
Recognition of prior service credit (1) 0 1 1
TOTAL PERIODIC OTHER POSTRETIREMENT CREDIT (4) (9) (8) (18)
Cost capitalized (2) (2) (3) (3)
Reconciliation to rate level 3 4 5 6
Total credit recognized (3) (7) (6) (15)
CECONY | Subsidiaries        
Defined Benefit Plan Disclosure [Line Items]        
Service cost - including administrative expenses 2 2 4 5
Interest cost on projected other postretirement benefit obligation 10 10 20 21
Expected return on plan assets (13) (13) (25) (27)
Recognition of net actuarial gain 0 (4) 0 (9)
Recognition of prior service credit 0 0 0 0
TOTAL PERIODIC OTHER POSTRETIREMENT CREDIT (1) (5) (1) (10)
Cost capitalized (1) (1) (2) (2)
Reconciliation to rate level 2 2 3 4
Total credit recognized $ 0 $ (4) $ 0 $ (8)