XML 173 R144.htm IDEA: XBRL DOCUMENT v3.22.0.1
Fair Value Measurements - Reconciliation of Beginning and Ending Net Balances for Assets and Liabilities Measured at Level 3 Fair Value (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning Balance $ (19) $ (16)
Included in earnings (9) (10)
Included in regulatory assets and liabilities 3 (7)
Purchases 6 0
Settlements 5 15
Transfer out of level 3 3 (1)
Ending Balance (11) (19)
CECONY    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning Balance (10) (6)
Included in earnings (3) (5)
Included in regulatory assets and liabilities 1 (4)
Purchases 0 0
Settlements 3 6
Transfer out of level 3 2 (1)
Ending Balance $ (7) $ (10)